Honest question- why would you choose anything other than the UM rings for a Tikka, esp if you are having them mod the action/bolt? Assume starting from scratch- I can see wanting to keep rings if you already have them.
There’s a few reasons. Some rifles need additional elevation via a rail, and some like to swap optics back and forth that are mounted in rings already. Some scopes need to be mounted further back for proper eye relief and the direct mounts are too far forward.