at least the 475 on the rudder. can't remember the torque on the 425's.
the decathlon looks good for the cash, right. I checked one out at the LHS.
your putting a .75 on it? My ST .61 with a bisson pitts might have a new home. Let us know how it flys when you get it done.

for what it is worth, i had a 40 size decathlon with all standard servo and it flew fine. awesome snaps.