I was slightly worried when reading reviews on this mic cutting out (due to the 3.4 GHz band), but I'm glad to say I have had no problems in gigs - big and small.
I tried multiple other wireless mic set ups for my trombone, but all fell short because of a low SPL. Every microphone or wireless converter resulted in distortion when playing - even at low dynamics. With this system, though, I have had no such problems.
Another advantage of this mic is the low weight. If you've ever played trombone with a traditional wireless mic pack, you'll know that after a while it can get tiring. This system is so light that I barely notice it, which makes gigs feel easier.
The sound quality, which I tested in my studio, is also very good when you consider the package it comes in. There are no sacrifices made when it comes to pretty much any frequency range, which gives you lots of options.
The only thing I would recommend is that you don't connect the receiver directly to the mixer, but rather to the XLR that you would have connected a microphone to. This way the receiver is close to you and it limits the possibility of dropping out.