This is for the aforementioned 70-200 f/2.8L IS that I wrote about a few posts down.

German made...really high quality. Link below.

Whether it's worth it is up to you, but the B+W filters are constructed better than the others I have seen.

I was reading a thread on FM last year, where a college photography teacher had posted some examples of pictures students had submitted using inexpensive circ pol filters. He was of the opinion that it was worth the added expense to get the higher quality filters.

*edit*
Just realized you're looking for a UV filter. Honestly, I doubt it matters. They don't do much anyway. B+W is still constructed better than the others, but a Hoya should suffice and it's still reasonably good. I always see people advising others to get the coated filters...my understanding was the coatings increase light transmittence, but don't reduce glare and reflections between the front element and filter. Do a little research on that aspect, because if that is true, the non-coated filters will save you a bit of cash.<ul><li><a href="http://www.bhphotovideo.com/bnh/controller/home?O=productlist&amp;A=details&amp;Q=&amp;sku=9778&amp;is=REG&amp;ad dedTroughType=categoryNavigation">http://www.bhphotovideo.com/bnh/controller/home?O=productlist&amp;A=details&amp;Q=&amp

at the cost of a minor loss in light transmission ( &lt; 1%)

Because instead of reflecting the light, the light is transmitted.<ul><li><a href="http://www.canon.com/technology/s_labo/light/003/03.html">http://www.canon.com/technology/s_labo/light/003/03.html</a</li></ul>

when i saw stores and manufacturers quote things like "99.7% light transmission" on filters, i thought that it meant it had a minimal effect on blocking light.