Best OPK brand?

Sarah
Hi ladies, I am planning to start using an OPK after my next period. I tried using a generic drugstore brand in the past and am not entirely confident I got accurate results, but who knows. Any recommendations on whether it's worth it to buy name-brand kits, like First Repsonse or ClearBlue? Or are generic brands ok? Any suggestions or recommendations welcome and appreciated. Good luck to all of us!