Apparently (according to our sound guy) these systems have a limited life, and 5 years is about right.
Right enough, after years of being rock solid it started dropping out just before Christmas, and now it's more like it drops in occasionally.
The G70/75 is a redesign, and looks quite cool with some new features. I was planning on holding out based on the new switching capabilities of the G70, but a cheap A/B switch will do the same job, and the Shure automatic channel selection feature looks like it would provide reliable performance.