This was my first wireless in-ear system, so I guess that I can give a newbie, yet unbiased opinion.
It was very easy to assemble everything even without instructions; upon first usage, you turn on both transmitter and receiver, and they immediately find the matching frequency. It was that easy indeed, really plug and play for me.
Used it both at rehearsals and at small gigs - a bit noisy only when it's completely silent around you, when the music kicks in the noise is easily overwhelmed.
The only (small) minus is that the battery charge indicator seems to work badly, it always shows half charge even when you insert fully charged batteries. Nevertheless, one set of batteries lasts for about 4-5 hours.
One final comment about the headphones: I cannot understand why everybody claims that they are rubbish.
If you're not looking for perfect sound insulation, in my opinion they are pretty decent. Maybe that's because I'm old fashioned and I like hearing what happens on stage, and I use the in-ears only to help me hear my backing vocals more clearly. But I don't think you necessarily need to upgrade them, if you use the in-ears as I do.
Recommended!