Thanks to everyone for their advice! I looked at a few more cars over the weekend and still have the same two as the best finalists. Here's a little more about the two cars: (forgive me in advance for excessive run-on sentances)

1) a 1990 190e 2.6, 89,000 miles, the car lived in Texas until 1995 (I'm in Minnesota so a salt-free car is nice to find), one owner, a couple that is now retired and the car isn't driven very much particularly in winter, very nice people that I seem to be able to trust, complete service records, everything works except the power antenna and the rear left window that has been disconnected because it would lower but not raise (window regulator bad), car drives great except it seems to have warped front brake rotors (vibrates upon light braking), body is immaculate and in very appealing colors (smoke silver with creme beige tex), has an aftermarket CD changer that plays thru the stock radio. Asking $7,900.

2) a 1992 190e 2.6 with only 60,000 miles, has recently had its head gasket and motor mounts replaced, two owner car with complete records, current owner was kind of arrogant. The car has ASD, the car drives perfectly (strong brakes) and everything works, body has a few scratches and dings (nothing major, just little pimples here and there), comes with second set of winter tires, green with parchment tex, asking $7,500.

Here's the quandry:

Either car would serve well. The 92 has less miles AND is two years newer AND has a lower price, but I find myself preferring the 90. I have more comfort with the owners, and frankly I like the color combination a lot more. But likely the brakes need attention and I'd like to have the rear window fixed.

Questions:

On the 90, how much would you guess to have the rear window fixed? The brake rotors turned (or replaced)? The pads were new last summer so they should be fine.

I've seen the advice to watch out for the head gasket. On the 90, it doesn't show evidence of leakage or anything obvious, how would I check for any imminent failure? Once it's replaced (as it has been on the 92) is it a problem that recurs every XX miles?

Both cars have a very poorly-fitting glove box door along its left side, is this common and can I adjust it or tweek something to make it fit better?

Any significant changes that occurred between 90 and 92? The only things obvious are the addition of ASD and the deletion of the vaccum gauge. How worthwhile is the ASD?

Further advice or opinions from the group? Thanks again, in advance!!

Dave