We used Xvive, Line 6 G10s and G30, a Carvin UHF system, and the Shure GLXD16. The guitarist with the Xvive now uses the Shure. I still use the G10s, and the other guitarist uses the G30. Our experiences:
1- too many drop outs on the Xvive.
2- Both the G10s and the G30 can be susceptible to dropouts, but staying close and watching what is near the receivers is key to minimizing it.
3- The G10s auto channel select doesn't work well when other 2.4ghz wireless units are in the band. For the auto select to work, all the other units need to be up and transmitting. I gave up and coordinate with the G30 guy on the channel selection.
4- The G30 eats batteries. The guitarist usually turns off the transmitter frequently.
5- I've broken the G10s transmitter because it's rigid unit unlike the swivel capability of the Xvive.
6- The sleep mode of the G10s transmitter can be a pain if you have pauses between songs on a set. Worship bands as an example.
7- The Shure works the best, but it's also the most expensive one. I guess you can say you get what you pay for when it comes to wireless systems. More money, less hassles.
8- Digital sounds better than the old analog Carvin UHF system.
9- Also buy a 2.4ghz system that can use frequencies outside of Wifi channels 1-11. If you are in a region that allows channels 12 and 13, I don't know what you can do, but kept the receiver close, and not near any other wireless systems.