I bought the Line6 Relay G30 in March ´11 and it still works as good as on the first day.
The Line6 uses the 2,4Ghz frequency to transmit the guitar signal to your amp.
Although the cases of the transmitter and receiver are made of plastic they don't make a bad impression. The power adapter is very good.
The G30 has 6 Channels to use, so if your bands member want to use it too, it wouldnt be a problem at all.
Some facts that I realized in this time:
I always could trust in the batterie status display. So if your batterie is going to stop working, it will show you .
The Cable tone simulator is not a must have. I don't use it all, works for me fine without the simulation.
I only use rechargeable cells, to save money und the environment. But the problem is with those cells, that they are obviously a little bit taller and thicker than normal batteries. So its pretty hard to close the batterie case because it is very small measured. However, it works , its only a little tricky.
If you want to use the G30 at home, make sure to choose the right channel. Some channels disturb the WLAN connection because it sends signals on 2,4GHz too. But I always found a channel, so WLAN and G30 work fine with each other.
The performance on the stage is good, never had range problems or any other problems at concerts.
I also couldn't hear a difference between cable or G30.
In future I will buy some transmitter, so I have the opportunity to use my 3 guitars with one system.
So if you need a stable and trustworthy system, go and buy it.