Aelanu,
I would stay away from blue dyes just because the majority vote is that they suck!!! LOL! I personally have NEVER gotten an evap from a blue dye test but I wouldn't take the chance now that I know what has happened to so many of these women.
I trust the Dollar Tree ones. Ive used them plenty of times and Ive also never gotten an EVAP from them. Even when Ive gone back and dug them out of the trash 3 days later just to look (like we all do...LOL).
I have actually ordered all of my tests recently from early-pregnancy-tests.com
They offer "conception packs" where you can get better deals on the strips. They also offer the ones you pee on vs the strips you have to dip. I buy the strips, cause they're the same thing, just not in the plastic casing.
But anyways, I buy the pack #2. You get 25 OPKs and 10 HPTs for $25 with free shipping. They do have other combo packs if you want more HPT and less OPKs.
Just a thought and a place you could look.
Oh, and I found this website called peeonastick.com where they cover everything that could/should give you false+/false- results. She dipped the strips in everything....water, breastmilk, blood, etc just to see if she'd get evaps or false results. It was very interesting.
Hope this helps you!!!! Good luck!!!!