I have the 101 and I am getting 312fps with 367 grain arrows. I had a WB and it was 310fps so I am assuming another 2fps with the limb driver. Have you tried distance yet? That's when you really really appreciate the speed. For me, it was HUGE. I had a 9 year old Hoyt with very heavy arrows. At that speed, you should be able to take it to 40yds with the same pin???