I don't remember which brand I used but it was a name brand. I also track my cycle which helps a lot! They do come with instructions on which days to start to use them. My cycle is about 25 days and I got a positive around day 10 and, low and behold, I became pregnant! My recommendation would be to buy the one with the most tests in your budget. The kind I bought also pretty much said to wait until the test line is as dark as the control line so if your iffy on that a +/- test may be better for you. Good luck!