I don't know if I'm too late, but those MB Quart speakers are awesome. You don't actually need component speakers, but that is a great choice. I'm all for that choice. The Phoenix I actually haven't heard of, but you can try them if you're aiming for above stock. Most speakers, even some $17 pawn shop speakers I bought a while ago, sound better than stock. In fact, those replaced 97 SSEi Bose speakers.
I use the next step up from the previous poster, the Infinity Kappa 5.25" speakers. They're amazing. But if I had to do it all over again, especially since I've seen that MB Quart price, I'd go for that 100%.