I absolutely LOVED mine.  Had it for 2 years with ZERO issues.
It's NOT a club mixer, or a gigging DJ's mixer - it's a MASSIVELY featured bedroom DJ mixer.  Keep in installed in one place, and it'll be fine.
Re: the cross-fader - I was surprised at how good it actually was.  It is nice and loose - great for scratching.  It's a Behringer proprietary fader (X1 Infinium) and they currently go for £25 (bargain).  The cut in is not great (cut in is a problem on ANY fader that is not fully adjustable), but it's easily adjustable by doing the "Credit Card Mod" (check Youtube for how to do it).
It's definitely NOT a piece a crap, and once you do the credit card mod on the fader, scratching will be a pleasure!  The only issue with scratching, is the placement of those eq kill buttons... 
You will not find a more feature rich, and FUN mixer for anywhere NEAR the same money.
Combine scratching with the 2 FX units and the sampler, and you are SERIOUSLY gonna have a BLAST. 
(If I ever had to sell my DJM-850, I'd be buying a DDM4K without hesitation).
 
			
		
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