[EhsanGT]

The only "best" recorder is to have a data engineer and a full DAQ at your disposal. Assuming that's not in the budget, then the options mentioned are all good.

The Garmin is a driver coach, not a data system. Like 5.Monster said, it's extremely good for trying things lap after lap and figuring out what works and what doesn't based on the delta time. After the session, the data it gives you is useful for the time you probably have to absorb it and learn from it before you go back out. It's a great device and I use mine at all trackdays.

A proper DAQ or the PDR is just that, a data recorder. You need to be able to interpret the data and know what to do with it. If you do, then great. If you don't, then it'll just lead to confusion.

Garmin + PDR is a great way to cover most of your bases.