If you ever run an engine with one of these mufflers, you would see that they are worth the money. A Stock Evolution .60NX picks up close to 3,000 rpm over that of the stock Evolution supplied muffler (I have ran two Evo .60NX's with a Jett Muffler and the Junk Stock supplied muffler). You get what you pay for, and this muffler is built second to none. A Full length tuned pipe will cost you more, and require alot of tinkering, and in the long run not return much more than the Jett muffler.
I would rather pay the dollar's and get this muffler, since it is, engineered, tested, and manufactured in the Goood Old USA, than a Tower Muffler. I have Nothing against Tower Mufflers, since I run several, but you do have rework them a little to keep them together. The Tower mufflers will give you about 1,000 rpm over a stock muffler, but one of these does quite a bit more.