Wow. The timing is perfect. I just bought two pair. Well, I bought one pair, returned it, and bought another. Here's a quick review of the two models, in my (really blunt) opinion....
Sony MDR-RF960RK:
These things work up to 150 feet in distance. What they don't tell you is that the 150 feet is only line of sight, perfectly stationary, with absolutely nothing around the transmitter or receiver other than air for at least twenty feet.
I got really severe noise bursts as close as three feet from the base station. There were two large dead spots within line of sight just walking across my living room. (Note that this is wood construction, not concrete or brick, so that's just sad.) Even when I tuned it (it had a button to cause it to seek for the signal), it always had a high frequency whine that suggests that it never really found the center frequency.
For its power switch, the headphones turned themtselves on and off using a switch in the headband. Cute design, but can you say failure waiting to happen?
And then there was the flimsy power contacts. They pretty much felt like I was going to break something the very first time I put the headphones into the cradle. Really, really cheap construction.
Finally, I had to turn my headphone output WAY down to keep from oversaturating the crappy electronics in their transmitter. This, of course, meant that the headphones had to be turned fairly hot, and thus every one of those noise bursts was literally painful.
To make a long story short, I have never in my entire life seen wireless hardware that sucked this hard. Even the old 49 MHz realistic wireless mic worked better than these things. I don't know why I expected anything better from Sony, given my past history with their gear, but for some reason, I ignored my gut and bought this piece of garbage anyway....
For $100, I expect something at least halfway decent. Now I'm not saying I could design one that worked better. No, I'm saying I could have designed one that worked better when I was 10.
JVC HA-W300RF
This was the replacement. It was $20 less than the Sony. JVC claims 328 feet, and I think I believe it.
This has two minor disadvantages over the Sony, which I'll mention first. First, the JVC uses a (possibly custom) NiCd battery, which will eventually die and might be hard to replace... but not that hard, I don't think.
Second, this unit might have a slight disadvantage because of its manual tuning wheels. According to one review I read, it suffers frequency drift as the battery voltage decreases. I haven't used it long enough to know, since they shipped it with the battery basically drained, but that still gave me about five minutes of testing---more than enough to do a good comparison with the Sony (which I began boxing back up after less than a minute of actual use...).
Now, the positives. It has a real, mechanical, push-on/push-off power switch on the headphones. Major improvement.
The charge contacts seem really solid. I had a little trouble getting them to make contact initially, but at no point did I feel like I was going to irreparably stretch some flimsy spring-brass contacts like I did with the Sony....
From what I've heard so far, the sound quality is orders of magnitude better than the Sony. There's no constant 'slightly-off-frequency' whine, it doesn't lose its frequency lock whenever you turn your head or walk more than 3 feet from the base station, and even works reliably when the transmitter is on one side of my flat panel monitors and the headphones are on the other. Oh, and they sound better, too, even ignoring the artifacts. (The Sony had higher maximum frequency response @22kHz, but from the way they sounded, I think they pretty much lacked anything else.)
With the exception of when the battery bottomed out and the thing went into static hell (this is normal), I didn't notice any significant noise problems at all while walking all around my living room.
Relatively speaking, it's heaven.
I think that pretty much sums it up from my perspective....
