Apologies for the Threadomancy, just thought i'd give an update on this gun, and its issues.
So, the MOSFET in my TR16 CQW burned out on first skirmish (back in 2014) using 8.4v nimh. MOSFET was replaced under warranty by the retailer, with a replacement G&G MOSFET.
The 2nd MOSFET lasted 4 skirmishes before burning out!!! Again, using 8.4v nimh. Back to the retailer, who replaced it with NEW spec G&G MOSFET (which took a few weeks to arrive), they also recommended i use higher voltage batteries, as using low voltage was straining the MOSFET, apparently. So been using 9.6v nimh ever since. This new spec MOSFET is still going (touch wood!).
Have had another issue recently though - was getting 110fps, rather than the 300+ usual... gear box was cracked, visible in mag well, just behind BB feed. Luckily, i took out the 3 year warranty on the gun when i bought it - worth every penny of the extra £30!!! Apparently, due to the short barrel, they use a heavier spring on this model to up the fps, and it takes its toll on the gear box housing. Seems to be a common problem with these as the tech guy knew exactly was it was as soon as it said the model.