I beleive OS engines over rate the horse power listed in their specs more than super tigre engines do.

But IMO, the sound super tigre engines put out with those big bulky mufflers are somewhat annoying to my ears! Plus the mufflers have a tendency to fall off unless they are secured on very well. And you can almost guarantee the disc like baffle on the inside of the muffler will come loose and start rattling and when it does, it's a devil to get out.

big dan