This is a very good question and exactly aligned with what Weatherford Cementing Product is providing. Now that the technology has evolved so much I would say it depend on the type of DV tool you are looking for, the environment and the purpose.
Please may I also suggest you to have a look at the ISO 14998 V0 criteria.
If you contact your local Weatherford rep, I'm positive that he will be more than happy to answer your questions, share with you track records, share experiences and help you resolve your issues.
Please let me know if there is anything else we can help you with.
You can also check the Archer Cflex port collar, probably similar to the tam one. They have documentation on qualification as per ISO 14310 VO, NORSOK M-710 (ageing), NACE MR-0175 and others.
Agree they have not traditionally been used exposed to production or long term service, but technology might be catching up...
I've checked but from both memory & copies, I cannot find a direct reference to a DV collar in a Barrier Policy (Of a Co that I've worked with).
My experience has always been that it needs to be covered up/put behind pipe at some stage before the well goes into service, even if it tests. Be that the next string or a liner lap. Basically you can drill ahead with a tested DV but not produce.
Hearsay gives a historically high rate of failure, and a perception that you are one o-ring away from failure.
In a production string - In the right circumstances (Well Pressure, location, quality product, track record), I could be persuaded by a decent assessment of the risks and the appropriate checks/outcomes on installation.
For example, it's a metal-metal seal with an o-ring BU, it has 500' of confirmed cmt above and a decent shoe below, it is tested to heck (Extra time? Inflow test?), only see's reservoir pressure not gas lift. You get the idea.
My one concern would be - what if it doesn't test - what then?