The M4M16 is a good overall gun for beginner airsoftes. This starter pack is so so as a whole.
Pros
Good FPS
decent accuracy
good RPM
good consistency
light weight
half the price of the ECHO1 M4M16 but almost the same performance

Cons (for starter pack)
comes with a low cap mag, so you will need to get a few mid cap or a high cap or you will need to refill a lot. the low cap only holds around 40 rounds.
The vest that it comes with isn't that great, (you can get a lot that are better)
comes with 8,000 polished .12 rounds. Use the .2g BBs

As for the gun itself
it has a lot of plastic compared too the ECHO 1 version.

Besides the fact it has a lot of plastic it is a good overall gun for beginners, i would recommend it as a starting gun



5 stars

The IUM4A1B, a very impressive airsoft gun. It sounds great and fires fast. Everything arrived in one piece, very sturdy gun. The hop-up is a little hard to adjust, a little problem not worth mentioning, but would just like to point it out. The strange thing is...it came with a attachable hand grip, but there wasn't a RIS rail on the foregrip except for the upper reciever. It is very accurate and the front and rear sights are adjustable. Mine, however, did not come with the special tool needed to adjust the front sight, but i think its not included to begin with. The manual was amazingly readable! it came with a layout of the entire gun showing different parts (internal and external parts) of the rifle. This is one of my favorite guns because it looks, feels, and performs great, I recommend this to anyone into airsoft. 5 stars

Nice gun overall, and the best gun I have ever owned. Be sure to use high quality polished BBs, or the gun will not work as well. Sight is so-so, and the battery is hard to put in at first. Very accurate when hop-up is adjusted. 4 stars

This is not only a great product, but a fantastic company to do business with. I highly recommend, primarily because of the customer service alone. I originally posted a review that I was not that satisfied primarily because the product quit working after only two uses. Resigned to the fact I was out the money, the company placed a courtesy call to inquire about my satisfaction. When I explained the problem, they were extremely proactive in helping me with my problem. It turns out that the wires only came off of the motor and it was a quick fix. It's a great product, has never even jammed and it of good quality. I only wish everyone stood behind their product as well as this company does. 5 stars

this is the best gun i have ever shot, the gunn is great, light weight,but i do recomend getting a hi-cap mag. the low-cap holds about 50 rounds, so you have to refil alot. 5 stars