Milo, I'm kind of the opposite. I see a powder at the store and I'm like "Hmmm, I haven't tried this one yet." And then I get it. I like playing around with different powders and my powder cabinet is starting to show it.
I've only come across one powder that I found completely worthless and will never buy again and that is 700X. Could be my powder measure but it didn't meter at all for me. Liked to clump up going through my meter. I gave it away to the neighbor.