Im fine with different noises as long as I know what/where they are coming from. So have you decided/purchased your replacements? Are you going to post pics of how bad the rear rotors are?I'm not surprised. That's the price you sometimes pay for having slots and holes in the rotors to may your brakes look good. Also, I believe the pads are higher performance than OEM, and that tends to mean "noisier" too.
Anyway, it will go nicely with the faint "wub-wub-wub" from at least one of my tires at 30-45mph. They're not cupped, as far as I can tell, and there is no vibration. I've been doing some reading, and it seems to be a fairly common issue with uni-directional performance tires. There are also reports that these particular tires (BF Goodrich g-Force COMP-2 A/S) get loud as they wear, and I concur with them. I can't complain, though. I knew there would likely be trade-offs with putting a tire classified as "ultra high performance all-season" on a daily driver, and for the incredible performance that these tires deliver, it's worth it. For me, anyway. Other people are apparently completely unreasonable, and they want an ultra high performance tire that is perfectly silent and lasts 80,000 miles.