I've never used the manual roller base, but have done C-41 on a Jobo processor many times w/o any issues.
If you use the rotary method, you'll use much less chemistry than w/ inversion processing. MUCH less. This will allow you to stretch your chemistry more, saving you some money in the long run.
Make sure that you're well stabilized temperature-wise when using the Kaiser hotplate. Unless specific degree markers are marked(and read true), you might want to take a day to head up a tray SLOWLY, allowing the water temp to stabilize after each adjustment. When you reach a WATER BATH TEMPERATURE of 100-102˚F, make a mark on the adjustment dial so you'll have it for next time
. Also, are you using a METAL tray? I'm asking because a plastic tray won't transfer the heat to the water like a metal one will.
I believe you can get great results using manual agitation and the Kaiser hotplate. But take the time to set up your system, and keep good notes on color chemistry usage.
cheers,
Dan