I shot these thru a chrono today. The bow had a dacron string. I shot two different weight arrows, one was 9.8 gr/lb and the other was 11.4 gr/lb.
The 9.8 arrow shot 173 fps and the 11.4 arrow shot 164 fps.
This is about 7-8 fps faster than my original Bear limbs using the same string. I did not try using a Fastflite string. I would guess that if I had used a Fastflite string the speed would be about 180 and 170 using the same two arrows. I will try a Fastflite string and shoot 8gr/lb to see what they will do. I expect that combo will get about 190 fps or so.
Jim's prices might be the lowest of any after market limb. His wait time is very short too! I saw another set he is making for another customer, these are clear glass limbs using zebrawood under the glass. They are going to look very nice. I will try to post pictures of them when he is finished.