Model power, by far. The only ‘good’ stuff they ever had were locos made by Roco (E7, E9, FA-2, Sharknose). The rest was all pure junk. The stuff they make today is even worse! Have you seen their F2A? It’s supposed to be an F-unit, but it has a nose like a C-Liner. It looks extremely toy-like, and every time I see one I want to stomp on it!
I would have to say tyco as well. i remember getting my first train set when i was like 4 or 5. It was the firefox. The one thing that stands out in my mind was the high starting speed, low speed of the loco. I think it started at like 50 SMPH. But on the other side, it maxed out at like 300. I still have it laying around somewhere in the box of extras. But in tyco’s defense, i may have been the super generic 10 step power pack that made it start at such a high speed.
Model Power. I had two of their N-scale GP40s and one of the Alco 6-axle units they offered. Interestingly, all ran fairly well, though unfortunately they couldn’t haul more than about two or three cars. Their new FP (with the metal bodyshell) isn’t a bad effort, though a better motor and finer wheels would have helped. Most of their freight cars were awful too - far too underscale. A pity, as the mouldings were fairly well detailed and the cars run ok despite the plastic wheels. Their ACF Cylindrical hopper isn’t too bad for the money - change the trucks and wheels, add some weathering, and from normal viewing distances they’d look ok.