Final Choice: FLOWMASTER 50 Series DELTA SS
Well, I ended up at a place called 'Mighty Muffler' where the owner, Mel, was the only one who took the time to answer a few simple questions over the phone and seemed to be fairly knowledgeable with mufflers, etc...
I had him install a FlowMaster 50 Series Delta Stainless Steel on the D90, along with a custom aluminized tailpipe and a stainless steel tip for about $250. A little more than I wanted to spend, but not the $500+ I was originally planning.
Impression so far... nice idle, a little louder than I wanted speeding up out of 3rd gear... not bad ... The guy said if I didn't like it he'd switch it out no problem.
Thanks again to everyone...!!!