Great little cars. Been road racing, RallyCrossing, and doing all manner of fun stuff in BG-based cars for years. Not going to be an over-dog in any auto-X class but they're pretty good handling cars out of the box that are simple to work on and as durable as an anvil.
A bit of background; the name "BG" refers to the chassis code this car shares with the 90-94 Mazda Protege which these generation of Escorts are based on. All of Mazda's small cars, including the current gen Mazda 3, are still a "B" chassis of some sort. The EGT's were basically a 90-94 Protege LX in hatchback form. The 1.8 BP engine, G5M gearbox, and basically all the suspension and brakes are straight out of the Mazda parts bin. The unique bits are of course the body, the interior, the fuel system, and a few other odds & ends. The base Escort and Tracers of this era got the 1.9 liter CVH engine. Stay away from that mill, compared to the Mazda 1.8 its a lump of sadness and disappointment.
Things to Look Out For
Body
Rust can have its way with these cars. They're 90's econo-boxes so you can only expect so much. Problem ares are the rear strut towers (they can rot out, pull the panel off the rear strut towers to see what condition they're in), rocker-pannels underneath the side-skirts (you really have to get up in there to look for it as the skirts can hide it pretty well), corners of the floor-pan (normal for any car of this age), spare tire well (if the hatch has been leaking for awhile and water has gotten in there it can be problematic), rear wheel arches (many of these cars up here in the salt-belt have no rear arches left), inner-front of the body behind the hweels (they can rust along the seams), and the front sub-frames can get a little crusty if the car was especially abused.
Powertrain
The engines are very stout, especially in stock form. As long as the basic maintenance has been kept up the BP is nearly impossible to kill. Aside from the usual check of things like the condition of the timing belt, fluids, leaks etc., some things to look for are oil in the spark plug holes (if the valve cover gasket starts failing the spark plug holes can actually fill with oil) and oil leaking from the distributor (the o-ring eventually dry out and start leaking, very easy fix). Almost all of these engines will make a "ticking" noise on startup at this age, especially if they have been sitting for awhile. The noise is coming from the hydraulic lifters. Mazda went to a solid lifter design in later versions of this motor starting in the 99' Miata because even when these cars were new the hydraulic lifters would get tickey sometimes. This is not something to be alarmed about. You can replace the lifters with new ones, update to the solid ones, clean out the old ones, or just leave them alone like we have on our B engine cars and not worried about it.
Some say the gearboxes are "weak", but I've also seen some pretty egregious abuse of them, so your mileage may vary. They're economy-minded transmissions, so expecting them to hold up to neutral bombs and stratospheric boost levels is asking a bit much. Synchros can get a bit grindey, and the if the mounts are shot it can pop out of gear since this is a rod-actuated trans (more on that in a second). The shift-linkages on these cars are not the worlds greatest design in terms of longevity, and if they rust enough they can actually fall through the floor. Replacements are still available through Mazda (at a near $200 price tag :/) but a better one may be a salvage yard away depending on where you live. Also note that some of these G5 transmissions take ATF and not gear lube. I believe a 95 EGT will take ATF but don't quote me on that. Any Mercon or Mercon V rated ATF will do. If its gear lube, pick your favorite synthetic 75-90 and go.
One of the biggest weaknesses of the poweretain is actually the engine mounts. They're awful. There's 4 on the car (transmission, passenger side, and front/rear torque mounts). The worst offenders are by far the torque mounts. If they haven't been changed they've probably de-laminated at this point and will allow the powertrain to flop like a Brazilian soccer player. Thankfully, the aftermarket has a couple good options for you. Energy suspension make poly-inserts that side right into the factory mount. If you feel like spending a bit more coin, AWR racing makes full poly mounts for all four corners. Be warned though, those will significantly increase cabin-vibes and they make installing the motor a bit more challenging as they done allow as much "wiggle".
Suspension/Brakes
Suspensions are also very stout, but do have a couple weak-spots. The factory springs can crack, and these was actually a TSB issued on this issue. The aftermarket should have you covered here; even aftermarket factory replacement springs will cure this issue. bushings will likely be worn at this point but that's normal fro a car of this age. The rear suspension can be a source of frustration because removing the lateral links involves taking off a bolt that runs through the knuckle. There's a 90% chance its seized in there. Thankfully, all the hardware is still available from Mazda and fits right in. Also, the rear toe-links can seize over time as well, require replacement (and the removal of that long bolt). Also check for rust around the trailing arm to body bracket. This captured nut can also be a pain to remove. You may also see an example of Ford cost-cutting under this car; some Escorts/Tracers came out of the factory with one adjustable toe link. Thankfully, there's plenty of these available from your local auto parts store or Rock Auto (the Mazda ones also fit).
Brakes are pretty standard stuff. The front calipers are actually kind-of cool because they have a "quick-change" design for the pads. There's 2 pins that hold the pads in the caliper. Pop those 2 pins out and tada! You can change your pads! The pics can get crusty over time though, so its recommend to clean/sand them every so often so the pads don't stick on them. The pins can also shift from time to time, so they're a good thing to check whenever you have the wheels off or safty-wire in for extra peace of mind. The rear calipers are also pretty standard stuff, but the E-brake design can cause them to seize, especially if you drive/race the car is a dirty environment.
Overall these are really fun cars that are under-appreciated by even the enthusiast community. They're never going to be looked upon in the same light as say a 99 Civic Si or a similar 90's hot-hatch, but there's a lot of potential in these little things. One of our favorite aspects of this chassis is how easy it is to keep them on the road. They're extremely durable little cars and parts are SUPER cheap and ALWAYS available. Seriously, go look at the prices for bits like brake calipers, suspension arms, and other stuff on Rock Auto. Its almost criminal how cheap the stuff is. And because Ford made about a zillion Escorts, there's tons of availability. Some of the GT-specific parts can be hard to come by (like the bumpers), but on the whole you won't have to look very hard to find parts for these things. And sharing the motor with the 94 and later Miatas means hop-up parts are widely available for the motor. There's plenty of suspension parts too if you know where to look.
Further reading;
Protege FAQ (great info source on all things B chassis)
Club Protege (solid B-chassis forum)
Ford Escort owners Association (only semi-active Escort forum)
Solo Miata (great source on the BP motor)
Hop-up Part Sources;
Pierce Motorsports
AWR Racing
Mazdaspeed (some go-fast parts from the BG protege are still available)
K-Sport/BC Racing/Ground Control (some of your better aftermarket suspension options)
BP Performance Specialty (Carlos "the madman" Rivera has been boosting these things to the moon, one of the of the few people I know actively working on this chassis. Look for him on the facey-space)
Sorry if I threw a lot at ya, but we've learned quite a bit about these cars in the half-decade we've raced them and its always fun to pass the knowledge on.