I started with a system similar to a Tormek. After a time and talking with other turners I switched over to a 1725 RPM, 8", 120 grit grinder.
As NB said, that's good enough for 98% of what you'll turn. For the other 2%, start with a little coarse sandpaper.
Many will say the edge from the Tormek will last longer. I sharpen by hand and I can litteraly turn off my lathe sharpen my tool and turn my lathe back on in 30 seconds. To me that's bearly stopping.
I used to take me a good 3 to 5 minutes with my old set up.