Mach 28
I have both engines the Axail 28rr and the Mach 28 I like the Mach 28 over the Axail
Mach 28 pros
lots of power in a buggy great power band
great fuel consumption 71/2 minutes 125ml tank
cons
runs hot 270f but this is normal for this engine and hasn't effected the longevity of it
you could removed 1 of the head shims to get it to run cooler but I wouldn't it isn't that much of a difference.
Axail 28rr
lots of power in a buggy great power band
cons
Bad fuel consumption 5 minutes 125ml tank
If I was to buy another cheapy engine it would probally be a Mach 28, 5min tanks doesn't help win races. But I have moved on form cheapy engines.