I don't like lav mikes for singing at all. They are meant to be speaking mikes, not singing mikes. Also, if you use any kind of monitors on stage you will get feedback problems to no end using a lav. They are not meant to be used at high volumes. They don't usually have a really good frequency response and can sound kind of telephonish.

The countryman you guys are talking about, is that the one that just fits over your ear, it isn't really even a headset? I just used a Countryman like that a couple weeks ago, so I'm wondering if that's the one you're talking about. Although I liked the ease of putting it on, I didn't particularly care for the vocal sound. I sounded like a TV news anchor or something, again, great for speaking but didn't really like the sound I got from singing.

Typically I use an AKG wireless headset. I forget the model number. I really like it but for one thing. It seems to really accentuate the really high frequency, causing problems with syllibant (spelling?) sounds. You kind of have to know how to EQ it, but for rock or pop music which usually has pretty bright vocals anyway, it does sound rather nice. Doing country music, I like a little warmer sound, so I've learned how to EQ it.