Im asking because I'm in the market. What do I need to know? Brampton vs. Newark, 3.3 v. 3.5 etc etc.
From my memories of my '94 Intrepid 3.3: I ran the car up to 140K. During that time, the transmission was replaced twice, steering rack once. When I sold it, the A/C was out and it needed motor mounts, and the door bottoms were starting to rust. I also had the usual problems with the crank position sensor.
The 3.3L was totally bullet proof and never even burned a quart of oil the entire time I had it. The original 3.5L in the LH's didn't seem to have such a long life span; the way it was explained to me is that the water pump often leaked onto the timing belt, causing it to break catastrophically. Since it was an interference motor, this turned the valve train to shrapnel. If you can find a 3.5L that was properly maintained and the water pump and belt were replaced when they were supposed to be, I don't see any reason why it wouldn't be as reliable as the 3.3L. I just looked at a 3.5L Gen 1 Intrepid a few weeks ago with 179K miles on it, but the body was somewhat beat up.
I owned the 3.3L Intrepid and a 3.5L 300M at the same time. The 3.3L seemed to have a little more low end torque, but it also ran out of breath sooner. Obviously the 3.3L in the lighter Intrepid got better gas mileage.
I still have the 300M (a second gen LH) with the 3.5L engine and it's been a fantastic car. It's getting close to 100K miles, so its time to change the belt and water pump.
I hope this helps.