First off BY006B is not the full steel RK-06S, but the regulat RK-06. Since Dboy full steel rifles do not have a steel barrel, I won't count that.
Overview this is the Dboys clone of the VFC AK-74. Expect to find a Dboys style cocking handle (I intend to replace with a mock bolt once I wire to rear stock). Construction is standard Pinned parts, the paint finish is more rough then the smoother finish on the VFC AK-74. Black plastic pistol grip with visible mold marks is a turn off, a Brown or bakelite pistol grip should be installed.
The Front sight is the only pot-metal part I could find. Surprisingly everything else, gas block, rear sight block, rear stock trunion, take down lever, bolt, receiver is made of steel. The gun is 90% steel, a future steel front sight is in order when I manage to break the front sight.
The magazine catch is designed for Dboys magazines, and it needs to be filed down to lock with CYMA/Mag brand AK-74 magazines.
The gun oddly wired to top dust-cover instead of the rear stock.
The hopup chamber is transparent clear plastic, it will be replaced, Dboys/kalash does not have good hopup rubber so that will be replaced too. The Mechbox is standard ACM quality, expect to replace the Piston/ piston o-ring, shim the gears.
The Dboys slings are a P.O.S with the D ring being too small to fit the sling head through to complete the sling.
I would say this is a slightly better buy then the CYMA AK-74 if you are willing to work on her. CYMA guns are known to be great out of the box while the Dboys needs slight work. But the steel content on this rifle is way more then CYMA AK-74 at the same price. I would not recommend this gun to a new player or those that are less mechanically inclined. However it does make a economic project gun for experienced Kalashnikov users.
Amazing AEG for the price! AEG is very solidly built and has next to no wobble. Unless you get a lemon, the AEG shoots consistantly, and the DBoys 7mm gearbox is very well put together. Like most China brand AEGs, there's too much grease on the inside, but clean it up and re-shim and you'll be able to go toe to toe with LCTs, Real Sword and G&P AK AEGs. You might be able to stay in the field as long as the gearbox parts are middle of the road quality, sadly no steel parts, but it's more than capable of handling thousands of rounds without fault.
Mine lasted +4,000 rounds before I needed to do any real work on the gearbox.
Accuracy out of the box is very good as well, again, provided you don't get a lemon.
Fit and finish on the exterior is far better than any other budget full metal AEG and it is a steel receiver which means it won't crack like the crappy zinc metal ones.
Buy this AEG and you will NOT be disappointed...unless you've only ever held a Real Sword, Inokatsu, LCT or full steel Classic Army.