hey eric
doing the same thing as you actually.
After alot of research i found that you wont notice any difference between RDA and DBA on the street. The RDA are a softer disc so they will wear quicker, however, they are alot cheaper. As you would of seen on the rda group buy. So its probably best bang for buck if you went with the RDA discs. This, in the end, is what i chose and have just ordered with the RDA group buy batch 49.
I got told the best combo if what your doing is mainly street driving is RDA slotted with green stuff pad. Which is a less aggresive pad so it wont eat away at the rotors. They are more than capable of a few track days here and there. But if your after a tracked only car the you would have to go red/yellow which are made from harder compounds.
Just my 2cents
hope it help eric.