Where is bruce on this thread! Or swamp. Ill leave it for them to do their ceremonial explanation of thrust and wheel torque lol. Bottom line is when you are WOT in the m3 in the appropriate gear, you never see below 6k so if you are under 6k you have not selected the right gear.
ie for a highway pull the m3 at 75 mph in 3rd would be 5800 and get full use of its 6k-8400k powerband. If the M3 started in 4th it would be a lot slower. Whereas the 335 can be in a higher gear without a big sacrifice in pull or has more wiggle room.
When in the right gear which is usually quite a low gear compared to a turbo car, the torque output at the wheels is higher than a moderate-high tuned n54. High tuned FOB tuned n54's than exceed. But a FOB, catless and tuned m3 in the right gear goes neck to neck with a high fob 335 (once 335 does meth on top of it than it usually can take it)
So Factory m3 plus 2k worth of mods (catless, drop in and tune) and you run with a highly FOB 335. You also get all of the other m3 benefits of looks, suspension and sound of V8.
The reason low end torque does not matter on this car is because if you drive it in the proper gear for acceleration, the tach never sees low or mid rpms. Its literally impossible since the tach does not drop below about 6k on wot pulls when each successive gear shifts.
Only from a dig is there a slight disatvantage but if you use launch control that is not true since it drops the clutch at 5k and well on its way to its powerband and again bypasses all the low-med range where power lacks