I received my grey M4-A in the UK yesterday. I've posted a short
build log.
The final build I came up with is Gateron black, purple/pink LEDs, and Skeletor caps.
I discovered a few things about it that I really like so far. The plastic used on the base is slightly transparent, so if you use in-switch LEDs you can see the light underneath the case. It looks very cool on a dark desk.
Also, the cut out for the USB port is very nicely done -- it's neat and the USB connector fits snugly. It feels like it won't break when plugging it in. The switches fit through the case holes extremely well, and again the fit is snug so they don't move about when you're building the thing.
My case, base, and PCB had no visible blemishes, I'm very impressed with the overall quality. This has made me forgo any other group buys for RAMA's upcoming Key Clack GB and the Massdrop M10-A!