I keep the B+W 77mm XS-Pro Clear with Multi-Resistant Nano Coating (007M)on this lens and remove it only for particular occasions or when using another filter

I use this lens with the B+W 77mm XS-Pro HTC Kaesemann Circular Polarizer Filter when needed which I bought as a combo with this lens

FYI be aware that the B+W UV Filter 010M has a greentint to it, so if you need clear and clean image tone then consider the B+W Clear 007M Filter

(haven't had a chance to use the 11-24 yet

what else is there to say? its awesome

I use this with the Canon 6D, and the new Canon 80D from time to time