The EB-7 is indeed the way to go. I got one about 9 months ago and am running it in my MacPro 1,1 with 7 cards. It is awesome.
I seem to remember reading something about the Gen II not being qualified for HDX but since you will be sticking with TDM I dont think it will matter.
There is absolutely no reason to wait around for a Gen II box as the Gen I is much, much more common and also fully supported by AVID.
There are two potential caveats I should make you aware of:
- If you are planning to run more than 5 cards you will have to budget for a new PSU for the chassis.
- You should also replace the front fan for a silent one. The stock one is incredibly noisy.
Regarding the PSU: Make sure you get a juicy one. Most EB7's are 6+ years old which is absolutely no problem as far as the components are concerned (it's just a rack with a couple of PCB's). But the PSU's will be knackered and not able to adequately power more than 5 cards under load.
I used to have a ton of unexplainable, intermittent Kernel Panics when running HD7. The crux was that all cards alwyas passed DigiTest which only tests the funcionality of all the chips. However, problems started arising when the chips were under load as they draw considerably more power then.
Because of the way each mix is evolving different chips on different cards will be allocated even if you are failry consitent as far as track count/voice allocation and plug-in usage is concerned. That means erratic behaviour is very difficult to pinpoint. A bad PSU can screw things up in more ways than one so if you buy a chassis and start having issues this should be your fisrt port of call.
I recently spent some long and very painful hours troubleshooting my system until a member on this forum pointed me towards the PSU as a possible cause (I should use this opportunity to thank Bob Nagy again for doing so).
Once I swapped out the PSU all of these problems went away. It is very easy to do only takes about half an hour.
Regarding the fan: I bought
this one which is absolutely brilliant and not very expensive at all.
I would definitely get an EB7. It works very well and prices for Accel cards are very low right now. I am surprised there aren't more people buying them at this point.