I have the 137 that has very little transfer .
I love it , but it would be even better with more transfer .
The guys with the 129 with apparently more transfer , which I cant figure out why , all think it is great .
I would go with the RTX LE if you can , as the shocks are great , and its only 4 inches less on the ground.
The transfer covers for the extra 4 inches , when accelerating , against the 137.
My last sled had 144 tipped rails , which are only about 129 on the ground on hard pack .
My previous sled was a 121 , which is the old short track standard , now the 129 is the short track standard.
I just thought I would need the 137 to help harness the power better , but with very little transfer it spins too much .