Just out of curiousity, what type of setup are you shooting out of it...draw weight, length and arrow weight?
29" draw length, 71lbs peak weight, 28" Gold Tip XT Hunter 7595's, 100gr points, that weigh 380gr +/- 3grs or so total. I haven't chrony'd it, but I'd guess that it's shooting a shade over 300fps. I've thought about going to 125gr points which would take my weight up to a 405gr or so, and my shafts are spined well enough to handle them. It'd slow the bow down a touch, but would probably be quieter and cause the string silencer to last longer.
Mike