I finally convinced my buddy with a 3905 Maxx to lose one servo, and he admitted he should have done it sooner, it does turn faster with one and he noticed right away.
He just so happened to end up using the spare steering servo for the shifter when he bought the 2 speed kit. The kit came with the cheesy micro servo DOA, stripped before he even powered it up! I did think that was a bad idea on Traxxas' part the first time I saw the new 2 speed setup...
Consider eliminating one servo, and possibly upgrading that one servo. It will definetely reduce stress on your BEC if nothing else.
All I have to say is that a jr9100t will easily outperform any stock servo or pair of them. That is what I run in all of the trucks I have, and I could not be happier, it is a quiet servo with plenty of grunt and quick too.