Sainsbury's pregnancy tests? As bad as people say?


So I was wondering, has anyone used a Sainsbury's pregnancy test and got a genuine faint positive and it wasn't a false positive? I don't know what to think with mine and after reading reviews online I'm not hopeful. But last night I took one and it looked like the false positives people talk about with a very thin faint but blue line, and then I took my other one today and its very faint (and if I was pregnant it would be sooo early!) but a thick blue line instead and it's only developed the thin blue line after the time frame this time.. I just don't know what to think though after all the negative reviews. What's everyone's experiences with them? I'm gonna try and get hold of some pink dye ones today or tomorrow