I use to have some Team Group extreme 3733Mhz and had it for about 3 months. When I first got the ram I could only clock it to just over 3400Mhz, the fastest I could get it to go was about 3600 and I did find I got closer to the 3733Mhz after a new bios update came out.
I bought this ram to replace some Kingston fury 2400Mhz, which I had overclocked to 2850Mhz, I have to admit I did not notice any difference in gaming going form my overclocked fury ram to the team group extreme. In the end I sold the ram and bought 32GB of Fury which only cost me £110 and overclocked it to 2850Mhz.