I too owned the Grizzly lathe you mentioned (for 5 years). I sold it to a guy who is using it to buff pool cues. A fitting life for the machine.
My problems with that particular lathe were:
1) The headstock would not lock in place. I had to drill & tap the bed and headstock casting to bolt it down with a strap. Needless to say this hindered swiveling the head, which I did every so often to turn larger bowls.
2) The drive belt shredded after 6 months. An American-made (Gates) belt solved that problem.
3) The switch shorted out (after warranty).
4) The tail-stock was sloppy on the bedways and could not be reliably aligned with the spindle no matter what.
5) The hardware (screws, bolts and levers) were soft steel, unworthy of being used on any machine tool. The lock-down lever for the tool rest stripped out. Once again a USA-made replacement part (from Carr-Lane) solved the problem.
6) The spindle is not plated. The spindle is not hardened. The spindle taper is not precision ground. The spindle is wobbly with run-out. Bummer.
7) The lathe motor is under-powered for outboard turning. Sure you can do it, but the motor stalls on all but the lightest of cuts. The slow going makes roughing out a drag.
I was "upgrading" my lathe to the end. I had to replace the screws on the belt cover (the heads stripped out). I figure I spent more time and money fixing up the Grizzly than if I had bought the 12-36 Jet to begin with.
To Grizzly's credit, they sell people what they want: cheap stuff. Then you either learn not to fall the "too good to be true" deal or you live in a constant state of dismay. I have to thank Grizzly. Almost from the moment I bought the lathe I wanted a better one. Each time I used it it drove my desire to get rid of it.
I now own a Jet 1642VS with a 2 HP motor. It cost way more than the Grizzly, to be sure, but I can sit down now because my butt is no longer sore from kicking myself. Did I mention that my work has improved dramatically? On top of that I can make better stuff faster. It's way way more fun to go out to the shop to turn on a good lathe with good tools.
BH