I know this post will be disagreed with, but...
KMC or Player's Choice are the best sleeves on the market. They're quality sleeves, and also aren't really more expensive than anything else. You may not be able to find them in your local gaming shop, but I'm sure they could order them, and if not they're available online. Go with these, and you won't be disappointed, I guarantee you. I've had a pack of the Peal White standard size (make sure you get standard size for Pokemon) for nearly a year, and not one has broken/peeled, and I've had to replace one because the corner was bent.
Below that, Dragon Shields are also okay. They're probably the "tier 2" sleeves, lol. Solid choices, but definitely not as good as KMC or Player's Choice.
Anything outside of those three brands (besides Professor sleeves) is garbage.