I would tend to agree with Richi on the fact that beat mixing by tapping the tempo is rather awkward. At least that was until I recently sold my urei and got a Xone 92. Right now my setup is two decks, the xone, my powerbook running serato, and my pc laptop running ableton. With live hooked up to the midi from the mixer, I find it very easy to match the tempo in live with the current track playing. The xone has at tempo tap that works quite rough but once you have the approx. tempo tapped in you just use the tempo adjust knop on the mixer to pitch live. It's very much like using the pitch on a deck except its rotary. Furthermore you can use live as a very extended effectsbox, and its very simple. And the sound quality of the effects is up to you and you wallet(the better the plug-ins and sound card the better the sound).
Well sorry to sway of topic here but to get back, I can only refer to serato as that is what I have. I haven't made any direct comparison but I didn't notice any degradation that sprung in my ear from first use.
Oh and finally, the sound of the xone is really very nice in my opinion. It's better than most other mixers out there but still the urei has that umpf in the bottom, and those smooth highs that just makes it special. As has been said numerous times its a question sound quality and features. It seems the urei sound is not reachable if you want eq's and filters. And that's just what I need right now.