What brand of card sleeves are most reliable for Magic the Gathering?
I have not seen any independent quality assurance tests comparing the various sleeves, and I sincerely doubt there is a comprehensive one to be found. It's probably not economical for anyone involved, since QA comparisons like that can be quite expensive.

From anecdotal evidence at my local shop, which has ~80 player FNMs every week, most players seem to agree agree that:


KMC sleeves (matte or normal) are generally the most durable.
Dragon Shield will start split during shuffling.
Ultra-Pro Pro-Matte will become dirty fairly quickly.


These are the three most popular sleeve types at the shop.