Dan ..... LOL ..... no I think your slightly wide of the mark (as I was at every apex at the MK GP .... is 2wd really that hard these days ...

)
I currently only have a 5.5R and a 6.5 bonded LRP and would like to have all my motors from the same source as it's easier to make a selection based on that and the Novaks seem almost bullet proof.
The throttle control thing though mate doesn't quite stack up .... if anything I'm being too cautious and soft with the electrics as the power delivery is a bit savage compared to the OS and Go engines I used.
Dan, actually if I explain my thinking then maybe you could sense check it for me
4.5R ..... for simple high grip tracks with long straights in 4wd
5.5R ..... general 4wd motor & simple high grip long track 2wd motor
6.5L ..... general 2wd motor & when it all gets slippy and technical with 4wd
7.5L ..... 2wd motor for ice, glass and soaking wet nitro covered astro
Does that make sense? Would you go for all 4 or loose one end? I used to use 12x2 and 13x3 as my main motors (BRM) in 4wd and 2wd respectively. I have always prefered a smoother motor than a snappy one ..... would never find a single in my motor colletion!