||So I recently bought this and this is my run down on it:
Some of the gun parts like the bolt carrier and hop up are covered in the factory grease that i would recommend cleaning off and putting your own on. Other than that it does come with an instruction manual that takes you through most of the steps. BEWARE THE INSTRUCTION MANUAL IS A LITTLE BIT OUTDATED AND DOESN'T INCLUDE ALL ASSEMBLY. The Instruction manual leaves out some things like the hop-up assembly.
-keeps you busy for a while
-worth every penny
-good stock recoil
-very nice feel to it
-good quality parts
-some parts can be very tricky if you don't know what you are doing (like me)
-be careful not to break anything while assembling. (some parts are really hard to get in)
-some parts might need extra items for them to work properly (i had trouble putting the gas system together cause some parts seem to be missing or something.)
conclusion: overall this is the best gbb m4 u can buy for this price. It is hands down amazing after you are done building it. This is well worth every penny spent and if you have the time, knowledge, and money and looking for a gbb rifle that won't necessarily break the bank this is exactly what you are looking for.
Rating: [5 of 5 Stars!]