On a utility level, it's what you'd come to expect from an m4. Good fit in my hands, adjustable butt stock, two sling mounts, standard iron sights, top rail for optics/scopes, appropriate sized barrel. The blowback action is very enjoyable and quite a bit more intimidating than the usual rattling away of an AEG. Bothe the lower and upper receivers are metal, the barrel is metal, the handguard is dense plastic that i have had no issues with. butt stock is a bit flimsier plastic and will crack from multiple hard hits to it. The gun itself is very customizable as you can outfit it with a higher or lower pressure valve for more or less velocity. You can mess around with the buffer tube for higher or lower RoF. The hop up unit can be quite a bit inconvenient to get to however as it is within the hand guard and it can be a bit tough to take off (no screwdrivers or anything needed though.) All in all, its a damn fun gun to shoot and for the price, probably one of the more affordable higher quality GBBR's on the market.
-Very customizable from the get go.
-Threaded outer barrel
-Rail for optics
-Open bolt easy to fix jams
-Pistol grip can get very uncomfortable from prolonged play
-Handguard makes it difficult to find a rail that will fit
-Magazines are very prone to damage causing your gas to leak
-Loading nozzle is plastic and can very easily break (the reason why I'm not using my rifle right now)
-Open bolt makes it undesirable to play in sand (I've done this, takes about 2-3 hours to fully clean)
-Butt stock material prone to breaking from falls