I'm looking at a couple of Nady wireless guitar system... anybody used one? any good? do they pick up much interfernce, what's their range, etc.? I had one of the original Samson models in the mid 80's and had some latency issues. How do the modern units hold up? At church where I'd be using this system we have a LOT of wireless (6 Shure in-ear monitors, 6-Sennheiser mics, and a coulple of other wireless things)... any know issues or problems?