No. What he's saying is if you're messing around with the exhaust, especially for performance purposes, use mufflers (so that you have enough back pressure and don't lose performance).

Even just for better sound, use the mufflers.

Basically, if your X is mostly stock or not heavily performance modified. changing the stock exhaust is probably going to net you lost power.

I have stock exhaust but replaced only the resonator with an x-pipe for the nice sound - didn't care too much about the performance hit.

If you don't have at least headers, you probably don't need to mess with the stock exhaust for performance gains.

That said, who doesn't like modding?