I agree on your earlier point in the context that very few realize the ET/MPH potential of their combo. To this point that is quoted, there are as many less-than-ideal single-4 combo's as there are 2x4. That being the case, generally the TR is worth more power at the start and more with tuning in my experiences. Once a guy 'learns to fish' (tune carbs) it's no more complex IMO.
