If you have BPM counters, hell turn em off! And for the synchronize button; i wouldn't relay on that one, it's crap and using it won't get you a place at a club
Vinyl sounds warmer indeed, the main reason is that a cd knows 'digital clipping' (bit convertors) which has a limit. So the music on a cd can't be loud technically. Compressing it (not the same as zipping a file) makes it louder, but sharper. Vinyl's can't clip, how louder you go how bigger the distance between the trails, so you get a warmer sound. Also the cracklings of dust and some soundcolor changing parts of the nice analog technique make the music come alive.
Mp3 is a lossy format, but you usually BUY your mp3's on beatport as a dj, in 192kbp/s. No-oone can hear the difference. There is a online test which you hear both original and mp3, from bad to worse. You have to guess when it's 2 times the original one. Everyone dies on the fact they chose mp3 and original. Even in a club, and trust me, you can't hear the difference. Roger sanchez, and many other dj's already take the advantage of it. Spinning mp3's, either with turntables or cdplayers is the future, (denon hd2500) and the whole market is gettin onto it.
But that's it for the technicians under us, let's stay on topic please, maybe we should chat in another thread, but show some gear!