ok, lets put it this way....why do most people hate the trx 3.3.
you are right, there is no best engine or best car or whatever. there are some bad cars, some good cars but nothing perfect. the trx engines are bad and even a true traxxas fan boy will admit that (btw, i dont want another flame war. another topic like this turned into a flame war with some guy basically saying the trx had no faults what so ever and ripping on me. needless to say, people with a lot more expierience quickly proved him wrong).
the nitro stars in savy's are also a very very nice engine. perfect for bashing, produce a nice amount of power and not too bad on the tuning front. a nice engine and certainly better than the trx.
then the mach 427, there is a reason why people actually buy this as an aftermarket engine for their trucks, its a very nice engine. and probably the best in an rtr currently. you can race it and it will hold its own againts the3-4x's more expensive italian engines.
i am not a brandist though, i go for what is the best. revo's drivetrain gets eaten by anything bigger than a .21. the savvy doesnt handle as well as i like (but, i do jump this off my roof into the garden, two floors) and the genesis is just a bit too big and cumbersome at times. my lst is my all rounder though. depending on what i will doing that day is how i decide what truck to take out, muddy hill climbing, genesis. need good handling, revo and major bashing i take the savvy. but most of the time i will take my lst out as it has a lot of the qualities of the others all rolled into one.
oh, and killer jato, looking at your name, appears you are a brandist