Depends on budget, if you got the money then a MyLaps system with their transponders is probably the best but it wont be cheap!

if you're on a budget look at an IR system, we use it at our smaller club. Its a lot cheaper compared to MyLaps at about 3500-4000 for the system and over 100 per transponder. Something like: https://trackmateracing.com/shop/en/...p-counter.html

It works with all the usual lap counting software, very accurate too.