The full mod has a smoother power band and gives a little more top end, you do get a little better fuel mileage but the depends on you driving and tuning. I have seen them go 8 to 9 gallons without any problems with good preventive maint, but as any motor is it really comes down to proper tuning and good maint. Trying to compare motors one from the other you will always get what someone else likes better, they are both good motors but I have had the best luck with the Extech .24 as far as performance and feel in a truggy.

As far as tuning goes on these motor, they are very easy to tune and hold there tune well, in most cases I only have to adjust the HSN 1 to 2 hours due to different climate changes and that is it.