For: G&G FS3/MK5 Low Profile Mount (LONG)Actually my cousin got this rail when it came along with his full metal G&G PM5A4 (MP5). Um, he doesn't have a sight but I did. I bought the Echo 1 MP5 A5 Christmas package. So yeah, I did get a rail (the "low profile", 35 dollar rail). During a woodland battle I asked if I could use this on my Echo 1 and I'd have to say I really liked this one much better. They are both metal and sturdy but I really prefer this one more.
-Very small so if you wanted to take the an optic sight off, you could just leave the rail on
-Very easy to put on (much, much easier than that $35 low profile one)
-The only reason I'm giving this a 3 is because this little piece of metal is $50... Its a bit REDICULOUS
If these rails were cheaper, maybe $20-$30, then I would buy one and give it a 5.
Unless you are a serious airsofter playing frequently and in need of a rail for your MP5 or you have $50 just laying around then get this rail. Now I'm not saying this is a bad rail and it's highly preferred and recomended by me. Its a bit on the pricy side, thats all.
Now, if your looking for an MP5 and are thinking of getting a rail and sight later on, go ahead and buy a G&G PM5A4 (MP5). It's a very sturdy, metal gun and shoots tremendously (hard and accurate) and this sight is included.
Hope this helped.