I picked up the CME wireless midi unit, mostly because it was $169., and I didn't have the cash to shell out for a midijet pro. it comes with two widi units, and a couple of short midi cables. My first impressions are that it does what it is supposed to, I'm not sure of the range, but it does let me go out in the crowd, and hear the house mix from out front before the show. This unit is not built like a tank (of course I compare it to the merge brick, which is a tank). I got what I paid for. The housing is plastic, and so are the switches for on/off and a couple of channel choices. It doesn't seem like it would hold up to any abuse, so I am careful with it.
One nice feature is that it can be powered off usb, if you're using a computer. I used this feature when I was running bfd off my macbook. It also doesn't eat through batteries very quickly, each unit takes two AA's, and they seem to last a looong time. There is an led indicator that glows red if it is on with no signal, and green when the two units see each other.
I would like the on/off switches and the channel switch to be easier to read, it gets confusing on a dark stage.
Overall the widi is acceptable. I've got wireless for less than 200 clams, and it does what I want.