The MP5A4 is a small sized AEG made for CQB, and it does its job perfectly. This little monster has a stock fps of around 340fps with a freshly charged battery. The RoF is average, but it doesn't seem to matter. The body is mostly metal, except for the front guard, and the stock. I've had this gun through around 9000-10000 shots already, and this gun still works fine.

Pros
-Fast stock Fps
-Mostly metal on external
-Small for quick movement
-Very light
-Durable (Mines been dropped a couple of times)
-Reliable (through 9000-10000 rounds)

Cons
-Version 2 Gearbox
-Not Many Upgradible Parts Compared to other high end AEGs
-No RIS or RAS
-HOP UP isn't the best around
 

Overall-8.3/10
For 140$, this is a perfect buy for newcomers looking to get into AEGs.