I was looking at one of those GDP scroll compressor kits on RA that replace the old pancake on an early 90's, but it seems people don't like the scroll type either.
(I don't know a lot about these compressors, so I'm unclear on the difference between the scroll and the sanden)
OP of this thread seemed to think the scroll was OK, but I don't deny
@L31MaxExpress' comment that they're inefficient at low speed... which may or may not matter to you.
You might search for "scroll" on GMT400, I swear I've seen at least one other thread with some discussion on that type.
Heat soak was mentioned earlier in this thread. GM addressed this on the
S10 trucks (at least in 1995, possibly on earlier S10 R4 deployments as well) with an AC clutch turn-on delay; the clutch would only engage after the engine had been running for... 20s maybe. When I was young and dumb I found this a huge inconvenience; now that I'm old and dumb I finally understand why GM did it. AFAIK, this delay wasn't deployed on the GMT400s, but I could be wrong.
(additional comments follow)
For those that may not understand (I didn't at one time),
Heat Soak is when the underhood temps climb after engine shut-down, which causes the AC high-side pressure to increase greatly in accord. This pressure rise isn't a major consequence until the engine starts and the AC compressor immediately engaged; then, the high-side pressures briefly go through the roof and, if there's no high-side cut-out switch to disengage the compressor, the atypically high pressures cause seals to be breached or other nasty consequences.
So to mitigate the effects of heat soak it helps to delay the compressor turn-on for a short while after engine turn-on. This gives the engine fan time to pull air through the AC condenser, reducing the refrigerant temp and thus the refrigerant high-side pressure, prior to engaging the compressor
This helps avoid nasty consequences.
For this reason I try to disengage the AC on engine shutdown so that it doesn't immediately engage on start-up.
$0.02