I use the 3005 and 3006 tanks for my 5x7 work and I turn them on roller bases. Yes, you should presoak for at least five minutes, but don't fret if the phone rings and the soak lasts ten minutes -- the duration isn't important, so long as it's long enough to permeate the emulsion. I don't adjust developing times for rotary processing. The effect of the presoak is to slow development. For B+W work, varying developing time by 10 percent doesn't seem to have a meaningful effect on my work anyway.
If you are developing 5x7s in the 3005, you can process ten sheets at a time with it! In the darkroom, join two sheets along their long side with cellophane tape on the base side, not the emulsion side, to create a single sheet that is 7x10 inches, and slide it in one tube. Repeat. When you process the film and remove the negatives at the end, the antihalation dyes will remain trapped underneath the tape. That requires a rinse of 45 minutes or so to clear the spots, but once the dye's off the negatives are fine. I've processed zillions of 5x7s this way without a problem.
Sanders