Debating

Have been reading this thread every day for a month, last time using was 6-7 weeks ago (mind you before that I was smoking all throughout college, 4.5 years), just failed a walmart test. Test is next week. I bought the 6.4 from urineluck website (can anyone confirm if this website is even legit?) Smoke shop bought 6.3 takes me to a different website. So I have both, smoke shop and online QF. I haven’t gotten the details of my test(can update when I get them) but when I called the place i’ll be testing at, they told me they have 5 and 11 panel rapid and 5 and 11 panel lab test? I don’t know which I’ll take, I don’t know if I will know which I’ll take. I guess my question is, Should I use the quick fix? Or should I try the certo method. Obviously i’ll do a test run to see if it will work with my body. But is the certo method effective? I’ve just heard a lot of people talk about that. I am scared of it getting flagged for synthetic or tamper, is there something they can test for that QF won’t have? is the temperature the only thing that makes people fail with QF? Any and all help, comments, shared experiences about passes and fails (what type of test/lab) would help.