M30 engines are pretty bullet proof if they haven't been overheated. I use the Alpina all year long (but not every day). It probably sees about 2-3 driving days a week all year long.

M30 engines also cost less to rebuild than a S38 and are less expensive to maintain and tune (no individual throttle bodies to calibrate & sync). An NA Alpina using an M30 engine is a very delightful car to drive.

You can browse more (older) Alpinas here:
http://www.m5board.com/alpina