We're still on 1.7.x and using TSM (not TSI), because we've found that to work well enough for the time being. Haven't tried 2.x yet because the investment needed to properly benchmark and upgrade would probably be around a week at our scale, and there are just more pressing things to do.
To be fair, we still haven't paid you guys a dime so I can't complain. But if you're interested in hearing my thoughts I can email you after next week's holiday.