I've got JL XR components in the front (6.5) and Infinity Kappa coaxials in the back (because they were cheap and I was sick of not having any rear fill.) I'm pleased as piss with the JL's. They REALLY scream since I installed an Eclipse 8051 head unit a few days ago. I've heard all the top of the line MB Quart stuff and wasn't too impressed. I've not heard the Diamond's though.