Improves cycling rate,
Easy to fit,
Look the dogs bollocks
Weaknesses:
Very easy to break threads when tightening.
Review:
First installed these beauties on my mech cocker and they really did improve my cycling rate!! dropped my trigger pull to about 3mm and i was firing 9 balls a sec over the chrono, which for a mech is no mean feet!
Very easy to install but i have found that not all qev's are equal,with some i have used not lining up correctly when tightened on the ram.This has resulted in me breaking a couple of threads off on the qev's and leaving the thread in the ram itself! not good at all!
The qev's themselves are an excellent product and with them you can see a marked improvement on BPS, i now have an E1 frame and the thing rips with qev's on.Anyone that thinks they don't improve a markers performance need to try them and see the difference they make!
Like i stated earlier ,the only downside is the thread being very weak, and if you tighten them more than hand tight they will crack..or break off (they are made of brass and are VERY brittle).This makes using thread lock/sealant a must to stop any possible leaks. i would gladly pay a bit more for a stronger version so as i don't have to worry about tightening them to the ram.
Conclusion:
Great product , looks cool, good performance boost for little money.
Need to be careful when installing,and use a thread lock/sealer to stop them leaking.
i give this product 10 for performance but an overall score of 7 due to the durability factor,these things are going to take some knocks during play and i would like them to be a bit tougher.