The G&G GBB M4s are actualy pretty good, the mags almost never leak and it has a decent kick. Ive had it for a year and only had 1 problem which was that the hammer spring flew off while i was transporting it in a backpack in two halfs. Its good for the price but it doesnt have a full cycling bolt, it only goes about halfway back if your looking for realism with the action then you might want a WE but i have seen multiple problems with the WE at my local field.