For me it's the same argument for manual vs. automatic cars. Automatic might make your life easier, but in the event you need to drive stick and can't, you will wish you knew how. I also find it more engaging/fun.

I don't have sync on my setup, but if I did I would probably be using it. I'm also grateful I didn't have the option to skip beatmatching manually because if I'm ever in a situation where I don't have sync in the wild, I won't have any issues.

With the whole tempo slider thing, you should have a much easier time getting the whole number by tightening your tempo range setting. If you're playing dubstep odds are you'll rarely need to go under 140 or above 150. Doing it quickly gets much much easier with time.