Several years ago the muffler on my 1988 Toyota 6 cyl. 4wd truck developed a pleasing rumble. Along with the noise there seemed to be an increase in power. However the tail pipe fell off the other day so I guess I have the choice of replacing muffler or breathing CO. I'm thinking I could maintain and perhaps increase the power by replacing the muffler with something with less resistance than the stock unit, Is Flow Master a good choice? Other suggestions?