As for DSP, I don't need it but the Crown comes with it. BTW, I think you're thinking about a different Crown than the one I'm talking about. The one I'm talking about does have DSP but it doesn't have an interface for hooking it up to a computer and programming it. I don't think it has any presets either. It's all done via the front panel and the settings are simple - stereo/bridged, xover on/off and frequency, x-over type, clip limiter on/off.
Basically I'm trying to decide if the Crown's ability to handle 2 ohm loads is worth paying slightly more for than the QSC which would give me more power but can't handle 2 ohm loads and is refurbished, at least in the price range I can afford. (Crown I can afford new, QSC would be a refurb)