You will probably want a new barrel(although I used the stock barrel for a year and it worked great.) and bolt. You might also want to sand down the beavertail.
Strengths:
-Very Reliable
-Easy to Clean
-Great Gun for the Price
Weaknesses:
The sight rail is pointless and the beaver tail is kind of awkward.
Review:
I didn't really know what to expect when i bought this gun, but after playing with it a few times i didn't regret buying it at all. The stock barrel works fine(it is probably the best stock barrel on the market) but you would probably want to get an aftermarket barrel for it. It is very efficient on C02 and has only chopped when using cheap paint(which will happen no matter what gun you have.)Overall a great gun for any player, newbie or veteran.
Conclusion:
A great gun for a cheap price. It works great right out of the box.