RE: Saito 91 in a pulse xt
You'll be happy with the 4S in your pulse. I have the XT 40, and I put the OS 70 Surpass II in it. I'm swinging a 12-8 prop, and I get great performance. I'd perhaps look at the Saito 100, a little more jam.
Good luck, and let me know how you like it. I have been thinking about selling the 40 and going to the 60.
Cheers,
HH