I have a JVC that came with my camaro, and an alpine that i put in my GP. The alpine delivers cleaner sound to my speakers than the JVC does. The build quality on JVC products is poor. They work, but everything else sounds better. I've ran both stereos on the same power with the same set of speakers in the same car, and the Alpine sounds better.
So lets see here: I own both stereos, and I've done a sound comparison using the same equipment and power levels. There isn't any doubt that most brands are superior to JVC.
Oh, and you're aware you said JVC's amps suck. You are aware ALL head units have a built in amplifier to power at least the stock speakers, right?
Unless someone else designs their HU amps and not their regular speaker amps...