Can't speak about the quality of Waldron's, but TTI systems are really impressive.
Todd Marsh at Marsh Racing beat everyone on price when I bought mine, if you decide to go duals.
The other thing I noticed is there is a very small margin of error where the mufflers push up. An inch eother way and they won't work.
FWIW, Todd at Marsh performance was about $80 less than Chicago Connection, who was second cheapest.