thevrclub
I believe they aren't technically available for commercial purposes yet; however, I've heard mostly positive responses regarding the durability of, charge time, etc. It uses the same base station 2.0 that the vive pro uses, so we had it up in running within a minute or two.
A regular of ours bought one and brought it in to showcase, it works incredibly well for some games, and not as well for others. The orientation of hands at times can be completely wrong, so many existing titles need to be addressed before it's a universal option in the way that Vive or Occulus are. If you decide to go with it, I recommend exhaustive testing of your library.
I would put the Index an extra half step above the vive pro. The edge to edge viewing is just better. Tracking is the same, audio is good and better than i expected from the off ear headphones. I really enjoyed the control grip in order to grab, it feels natural in a game like Super Hot. It can be less desirable in certain situations, but not overly detrimental. I'd be curious to try it on a wider audience.
We obviously don't need to upgrade at the moment, but I'll be watching for the enterprise pricing and warranty changes that come with it. As of now, it only offers 1 year warranty and it is so new there is a very limited amount of data on repair rate.
I'd say give it 6 months before pulling the trigger with that one. Newer customers aren't going to really know the difference without a side by side, but it's nice to have the "better" option available in a competing marketplace.