First Check Home Drug Cup Test Marijuana

Hey,

Just wanted to know how reliable the First Check test is that you can get from CVS?

If I pass the test with negative results, am I good to go and relax about going to take my urine test?

I know the First Check uses the 50 ng/mL cut off point. Do most labs use the same cut off, I know I read that there's like gas/chromo-something or other that uses at 15 ng/mL cut off level.

Also, I already have the paperwork for the name of the lab I would be going to, It's a generic one that's all over I think, If I looked at it and told yall the name could that help out?