I have now gigged this set-up professionally over the last few years and it has caused almost zero issues.
It is a single aerial system so you need to keep the line of sight to the pack decent, but the quality is great through my Ultimate Ears UE-7 moulds, which I run in stereo, and I have no complaints.
I use duracell rechargeable batteries in the pack, and this easily does 3 or 4 gigs worth, and the pack is light.
I had the pack replaced around 6 months in as the battery compartment flap would not stay closed but the replacement has been 100% fine.
Very good value for money, comes in a protective case (mine is rack mounted) and the other suggestion I would have to a buyer is look on eBay for a less bulky power unit, as I now have a much smaller one, which has been better.