My favorite is the the 1987 T-Top 442
I like it in every color it came in too. I think it's the best looking G-Body with the Euro lights, T-Top roof, bucket seats, console shiftier, Rally Pack Gauges and it came with 3.73s. I like most all of the G-Body Cutlasses, not the biggest fan of the grilles on the 78-80 Supreme but I like the Calais grill from that time. Sure the 307 is ho-hum compared to the Mustang 5.0 of the time, or even the TPI 350 L98 in the Camaro but an engine swap for an Olds 350 or 403 is pretty straight forward. Even stock I still prefer it over a 5.0 or 3rd Gen.
I really like the unpopular rarities too like the 1978/79 Cutlass Calais 4spd:
When I was in High School in the 90s I really wanted a G-body badly as they were plentiful and cheap at the time, but living in Rural New England a Jeep made a lot more sense. I did have a few buddies that had G-bodies and I think spending all that time around them back then set the hook. 3rd Gen Camaros and Trans-Ams were more flashy but there was something subtle about the G-bodies that just screamed tough without being too flashy.
I definitely still like the Malibu:
These weren't as plentiful as Montes & Regals where I grew up but my neighbor had a black one for years. Real basic interiors but the exterior proportions of this car just look right.
and the 81-88 Monte Carlos (The SS trim is least favorite exterior of all the trim lines though). The rears of the 78-80 cars look too droopy but the grill looks tougher to me.
Buddy of mine had a silver one just like the one above (no vinyl top and had the rally wheels too). He got rid of it for a 2wd S-10
Obviously the GNX,
Grand National and T-Type were the "best" of their day, and while I do love all of those cars, I don't really want to own one today. They are collector cars and to modify one with drive train swaps and suspensions mods it'd be a shame to do that. Putting LSx's in Malibus only increases their worth, while doing the same to a GN would just make most people cringe... I also want to be able to drive my car without having to worry about stone chips or dings. The ability to build these cars into fast street machines on a budget is really what still has me interested in them after all these years. So many parts are available to do stuff like LS swaps, crazy SBO Diesel block strokers, suspension upgrades and even T-56 conversions.