I ran a Prostar for a week about 5 years ago. For the amount of effort they say they put into getting the cab just right, it sure was a turd! The window switches were out of reach. In the 9400 I normally drove I swapped the driver window and door lock switches, and my hand fell right on the one I used most. If you forgot to shut the jakes off you had to stop turning the wheel in the middle of an intersection to shut it off. Same with hitting the air horn.
Then there was the little kick-up at the back edge of the hood. With the sun high over your right shoulder, it would reflect off that little patch of hood and blind you. 450 ISX 10 speed in it did pull WAY WAY WAY better than the 430 C15/13 speed though.
I didn't mind the 86 359 with 400 B model. The heavier it was loaded the better it ran. The 94 379X turned a lot better than I expected and rode nice. Didn't like the 15 speed though. 300 RPM drop between gears, never really got the hang of it.
9300 SBA with 444 big cam 3, I really liked that one. Tractor-tread floaters and forage box. It was loud. And fun.
FLD freightliner. Daycab, OK. I spent a couple years in a condo, I can get in one today and in 10 minutes I am in a bad mood. If I spend a night in a truck it's the same way, will take me a week to get any ambition back.
Couple R models, the one I couldn't find the tag for the truck, but the box was built in 72. Really liked the twin stick, especially when having to reverse a lot.
Really like the DT466 in a 4700/4900 IH for a smaller truck.
Favorite would be the 79 Brigadier tandem dump we had. 6v-71T Detroit and 13 speed, really deep rears. 65 top speed, downhill with a tailwind and a heavy load. Still got 7 MPG on a 120 mile round trip running 56,000 loaded. 18K steers, 38K rears on walking beams. Had plans to turn it into an RV/toyhauler and upgrade stuff like wheels and axles til I rolled it.
I really prefer the Big Cams and Detroits to the other motors. We have a Century factory daycab conversion with a 60 series and 10 speed at work, and I like driving it. Thinking of having it set up to a straight 430 (or whatever it can be set at) and swapping in a 13 speed.