The WS-MCR should not be confused with the WK-180C and vice-versa. Since parting company, the WS-MCR has undergone a significant redesign to address all of the known issues which still plague the 180-C. The incorporation of a press-fit steel "Wear Plate" on the Left side of the Upper Receiver eliminates steel-on-aluminum accelerated wear. The Cocking Handle is fully-machined with a beefy stem that fills the Cocking Slot and a deep recess in the Bolt. There are no reported issues with the MCR Pistons to date.
I was quite predisposed to write-off the WS-MCR as a cheaply-made econo-plinker, however since receiving mine I must say that I am instead increasingly impressed. Compared to my original Sterling-manufactured AR-180, the MCR is much tighter and sturdier-feeling overall. The recoil impulse is mild, the rifle is well-balanced, and reliability has been 100% out of the box for the first 200 rounds. Accuracy hovers around 2 MOA for 5 rounds of 62 gr PMC X-Tac ammo at 100m. What's not to like?
The WS-MCR is a solid, well-designed and built, Product-Improved AR-180 platform. Although I wanted to diskike it as a cheap knock-off, it is far from deserving of derision. To the contrary, with the latest factory upgrades (eg. a Cotter Pin now secures the Firing Pin within the Bolt-Carrier), the WS-MCR is every bit the raw perfornance equal of a similarly-priced AR15. The AR is still the more refined and ergonomic rifle/carbine by far, however their are some available upgrades that reaļly improve the WS to narrow the gap. The Magpul Zhukov Buttstock with aluminum adapter from SFRC for $200 is outstanding in all regards. The External Bolt-Catch and Release also works very well and integrates nicely into the look of the firearm. A Geissele Trigger to replace the heavy (but crisp) mil-spec example is also a must. I consider those 3 aftermarket upgrades to be essential for the WS-MCR. YMMV....
Don't bother with the WK-180C if you have not already conmitted. Although priced a bit higher, the WS-MCR is manufactured to a higher standard IMHO. The 2 rifles are night and day in terms of performance and reliability. Go with a current-manufacture MCR and you won't be disappointed.