Anyone done this before, are there any companies that do consulting for it?

Git repo's are ok, nothing too complex about moving those thankfully. Doing it the git way does loose work items however. We also have a lot of TFS repos and they seem to be hugely painful to move. The tools that get recommended are rubbish. TFS Integration seems to work, but then gets hung up on changesets. Opshub has removed any good functionality into their paid tool and left the free tool practically useless. We have around 60 projects so paying for opshub is not an option (Would be about $55000 using their pricing model).

Moving TFS repos to git is a possibility, but a lot of rework.

Anyone done this? What did you find? How did you do it?