I have had the opportunity of multiple events in a 1999, you are going to have a great time in your new car! Given the number of miles and you are a serial BMW owner you know the drill. I would get it on a lift when you have it home and do a complete inspection on the rear floor and differential mounting points. They are the weak link in these cars.
Attached is a picture from earlier this year.....
And yes, this is a factory slick top.