In reply to adam525i :
The M54B30 was my first thought, actually. S52 power levels, aluminum block, cheaper... but requires all the extra work that an S54 would.
After doing the research and thinking about it quite a bit, the S52 is just a lot less work. I don't really want another long, involved swap project right now. And the S52 has that 'X' factor of the factory E36 M Touring that could have been, but never was...
We'll see... it's all just BSing until I actually buy an engine. 
Too many posts without pics, so here's a random Touring pic...
Merry Christmas everyone!
