Re: Lavalier Mic comparison
This is my opinion, and you can take it or leave it, but I wouldn't buy any wireless for theatre that you can't put on an antenna distro. Without antenna distribution and good remote antennas, you'll have a lot of trouble with dropouts. There's nothing more distracting during a show than when the wireless is cutting out, popping, or otherwise acting up. It takes the audience completely out of whatever world you're trying to put them in. Better wireless will help with that, but you'll never avoid dropouts completely unless you have a distro and the right antennas.
Shure stuff is great, and that's what I have. You'll get more bang for your buck with Sennheiser though. In my experience Sennheiser is the standard for theatre production, from the top to the bottom.
If budget is a concern, the lowest priced wireless I would consider using would be Line6 XD-V75. You can run up to 14 channels, and they have a very reasonably priced 8 output antenna distribution box that when set up correctly can feed all 14 receivers, and their antennas are inexpensive also.
The suggestion to rent is a good one. That is, if there's a rental house in your area with good-quality stuff. Good wireless is expensive. My philosophy has always been do it right, or don't do it at all.
What's the rest of your PA?
Have you considered boundary or hanging mics? A few boundary mics across the front of the stage can work wonders, as can a few choir-type hanging mics dispersed well. A combination of both is great. There are a lot of options for hanging mics, and pretty much anything decent will work fine. As for boundary mics, the standard is the Crown PCC160. I have quite a few of them, and they're great for theatre. I usually space them 7-8' apart across the apron, and anywhere I can put one further upstage, depending on scenery.