I actually received my SC5000s today and I would. be happy to comment on some quick first impressions but nothing to in depth yet as I haven’t put in nearly enough time to form an overall opinion.
Quick preface: I’ve owned/used everything over the years from the days of lugging the crates of vinyl/Technics to Traktor via Kontrol S4 and Rekordbox via XDJ-CDJ units, (most recently the full NXS2 system, recently sold) over the course of a little over 15 years. Basically, like many of you, I’ve used a lot of DJ hardware over the years (insert “that’s what she said” punchline) and can tell the good apart from the laughable.
Build Quality It’s spot on. Heavy, thick, very solid feeling unit.
The most accurate comparison I can illustrate (verbally) for you would be as follows: If you’ve used both the XDJ-1000 (or 700) and a CDJ NXS/NXS2, you can immediately feel the difference in quality the moment you pick each up. Aside from the obvious lacking of many knobs/buttons found on of the NXS/NXS2, the XDJ-1000 feels like a hollow box with a build quality similar to a lot of DJ controllers. I’m not knocking XDJ-1000 (still use a pair as backups), just pointing out that is obvious to see and feel the difference the build quality right away
For me personally, as soon as I picked up the SC5000 it felt like Premium product, not a mid range unit a la XDJ-1000. It feels heavy, thick, extremely solid. It is a rock solid bit of kit. Not a cheap toy.
Here’s a couple pics I wanted to share:
The SC5000 consists of the single-piece top panel that resembles the top of the CDJNXS/2 and is bolted to a matted black, outer chassis. Both panels Have an extremely solid, weighted feel, the chassis especially. Bottom line, I don’t feel there was a noticeable step down in overall build quality from the NXS2 to the SC5000 at all.
The Pads/Buttons The performance pads feel excellent, definitely more of an MPCesque feeling in terms of texture/weight. I didn’t wasn’t letdown with their responsiveness either. Again, everything feels high end and has a strong, solid quality.
The Screen/Resolution It’s bright, smooth as silk (that framerate tho!!) and the touch/inertia feel responsive and quite natural. The high framerate cannot be understated. A pet peeve I always had with my NXS2’s was the choppy wave scrolling and how it differed at varying zoom levels, though It was never a real deal breaker for me. The SC5000 display looks and feels like the display on a smart device—the animation is buttery smooth and the touch response is equally smooth.
Aesthetically, while I don’t necessarily mind the blue/green/white theme/waveforms used throughout the HUD, it would be nice to be able to change to have difference palette options for the scrolling waveform—whether it be different presets to choose from or the option for the user to define. That said, I’m still exploring everything and it’s quite possible I overlooked an option to adjust waveform colors—if that’s the case please correct me (I’ll update if I find out otherwise as well).
That’s about all I can really speak to as this point. I loaded a couple tracks and messed around a bit, but nowhere near enough to formulate a solid opinion. For now I can at least say so far so good. 
You’re welcome to post questions (though I won’t be able to respond until after the weekend) and please feel free to post your own observations as well.
Cheers.
PS. It’s late and I wrote this on terrible small keyboard connects to my iPad, so apologies in advance for typos/botched Autocorrects.