I'm interested in this question as well. I purchased a Brita pitcher for our past trip but would love to hear some experience people had with the faucet mount version.
I debated between the facet mount and the pitcher for the longest time in Target. The facet mount was so much smaller and would be easier to pack in our suitcase. However, I decided to go with the the pitcher for two reasons. First, I didn't know how easy it would be to mount and unmount the filter with out all the resources from home. Second, cost. The pitcher was $18 and the mount was much more. The orig. basic model was even cheaper at $14, I thought the oval one looked like it would pack easier and was tougher. Also the Brita filters were cheaper then the Pur (at least the Pur 3 filters that Target had).
I was very happy that I spent the money and used my precious packing space for the pitcher and would bring it again.
I also packed our tea, cocoa and oatmeal mixes inside the pitcher so it wasn't too much wasted space.