update: on both the CalDigit site and at B&H, most of the T4 configurations are now available. Back in December, when I contacted CalDigit, they said it was simply a problem in their supply chain. I’ve read that there have been quite a few disruptions of this sort, in many industries. So who knows? That might have been the truth.
Meanwhile, Bob Z., do you have any insight as to whether CalDigit is still a good option? I’ve been very impressed, over quite a few years, by their tech support.
I don’t know if you’ve had luck purchasing the t4 but I’d like to give you my recent experience with the company. I had previously loved caldigit, customer service was excellent, I liked the design and reliability of their products until a few months ago. The t4 I had purchased about a year ago was no longer being supported on updated versions of osx. The driver that you need in order to operate the device would constantly just say updating. I contacted their support staff numerous times and they were even surprised that it had worked at all on my imac running Big Sur. They said they could possibly update the software but were focusing on future products. Such a shame really. You need to buy their proprietary drives, and use their proprietary software in order to use the raid. Literally can’t use off the shelf drives, they HAVE to come from caldigit. Luckily I had an old macbook air where I could copy the data off and a backup on backblaze so nothing was lost but sinking $2k into a raid only to have the company stop supporting it just under a year later is really disheartening for a professional setup. I would advise you to stay away.