I have made it a habit to always buy the UV filter of the manufacturer who made the lens
. Leica filters for Leica lenses, Hasselblad filters for Hasselblad lenses, Canon filters for Canon lenses.
First you can't go wrong (they know what they are doing), secondly you support your brand with a little extra profit.
How bad would it look to spend 2000 bucks on a fantastic lens and having to look every day at a lower-class UV filter on your Canon lens (because you wanted to save 20 bucks).