I had one in 9mm. Honestly, it felt like an AR15 knock off if that's even possible. The whole platform just didn't feel polished given the price tag. It's been a few years since I owned one so it's possible newer iterations have improved but look at the pic you just posted. When you mount iron signs on a rifle you want as much distance as possible between the front and rear sights. With the JRC I could only mount sights on the receiver because there were no mounting options for the handguard. My memory is fuzzy but I remember the handguard mounting system not accepting standard AR15 handguards.
I bought my rifle from a LGS, I forget who at this point, so I highly recommend picking one up and playing around with it. The JRC looks like an AR15, has similar features to an AR15, but somehow it just felt off. Like they could have spent some more time working on ergonomics or polishing it up a bit.
