As far as the selector switch goes, the only thing you change between draft load positions is the minimum eng RPM. The PTO mode will hold the pre-set PTO speed & thene there's the 'Off' position, where the auto part of IVT is sorta bypassed. You can change any switch position any time, anywhere @ any speed. You can even put it in reverse while going 26mph forward if you want.

I use a planter w/ two fans & a double hydraulic drive, but don't use the markers. I get by fine w/ a 1500 RPM min setting.

For planting, auger wagon & light tillage loads, the IVT, when working 'right' is a near perfect transmission. When it need re-calibrated, you'll be wanting to get it done ASAP. It can jerk & buck w/ any powershift, suddenly stop going down the road + do some really funky surges 'till you do. Not a biggy, just takes a knowlegable mechanic w/ a laptop. I first called to get mine done last fall, when putting on NH3. Finally got it done when I was ~ 1/2 done with planting beans. Took a second dealer to find a bad clutch switch during corn planting, before it would take the re-cal.

Don't expect the world for fuel economy & you won't be disapointed. The IVT is going to save you near nothing there. Using the tractors own gal/hr tach setting, you can see that you're not going to use much, if any more fuel w/ a virtually unloaded engine @ higher RPM (IVT off) as you will w/ the IVT engaged & a lower RPM. I know common sense dictates otherwise, but you have to see it for yourself.

I went from a 2001 7810 MFWD Powershift to the '05 7920. Deere quality took a MAJOR step downhill in those years - if not totally falling off a cliff. Lots of little things that are problems & common to all the 79's & a lot of 8020's. Faulty seat switches that turn the fancy seat into a no-suspension model to a cab roof with a built in leak that will be draining rainwater out on the side windows for two weeks after the rain event. The electric/hydraulic switches on the console seem to be another common issue. They changed them from the old proven design of the older 8000's & took something that worked near flawless to something that sometimes doesn't work at all.

My tractor has ~500hrs on it, is 13 months old & still has most of the same problems that it did the first day in the field. I've been working w/ two dealers & two different area JD service reps. As it stands now, I think Deere warranty has abandoned this tractor. 

 Overall a good concept tractor, but one I wouldn't own untill ALL the bugs are worked out. Mine is a lease, so I'm lucky enough that it'll be gone someday. No way will I consider buying out the lease on this particular tractor.