Regarding multiple gears, that doesn't necessarily mean 'hunting' will occur. The 6 speeds in my F150 and my Suburban hunt a lot less than the 'less smart' 4 speeds I had before. In our '05 Chevy, I was frequently having to manually shift from D to 3 to 2 because it would flop back and forth every 30-60 seconds. Partially because the gaps between gears were so big, probably, but the transmission didn't seem to have any programming to stop it. With my 6 speeds, I pretty much put it in D and forget about it. I would expect the 8 and 10 speeds to have similar programming.
