RG05- Hey, I do like the 54H's alot. I had SE255's- excellent low end torque and instant throttle jab response with those; pulled hard up to 4500-5000 rpm range, but low speed manners were slightly jerky in parking lot manuevers. That said, the 54H's seem to have milder manners at low speed. Instant roll on is about 300-400 rpm later than the 255's, which i personally like and wanted especially for two up riding with the wife. Her head doesn't snap back as hard now!! The mid and upper range with the 54H's is far better than the 255's. I like to wind it out, so the 54H's work better for me. I do not have headwork. Stock head gaskets, and stock pushrods as well. I had hot start issues with the 255s. That is gone. I also had start up bang and kickback, that is gone as well. The motor turns over just like stock cams did, which is a piece of mind as well. I had a starter replaced under warranty and figured i would eventually kill another after warranty ended. In short, the 54Hs accomplished two things- no hot start and no bang, and also alot more upper end pull. I am happy, but I do miss the instant snap of the 255s, as there is seemingly a half second delay before the 54H's pull. This is to be expected as the later intake closing value will bleed some compression as opposed to the 255s. I have been smarttuning with my SERT Pro tuner, and it feels so much stronger on mid/upper end. I am planning a dyno pull in February when my local dealer does free WOT pulls. The pull is like a two stroke powerband kicking in and it comes at about 2500 to 5800, which is so close to the rev limit i set at 6200. I bought mine from American Classic Motors in PA, off Ebay for $220, which was cheaper than Woods cams. Hope this helps, hope it gives you a better understanding, or doesn't muddy the water...