DSC-R1 Telephoto Lens

I truly love my R1, but I would like to get more reach (although I mainly shoot landscape). The Sony proprietary telephoto lens (w/adapter) is a joke for manageability, and it doesn't allow for zooming. I have found, however, a possible alternative in the Sakar 67mm telephoto lens (sale price $299.99 @ Abe's of Maine. It screws on the R1 lens like a filter, so it should also allow for zooming.
Has anyone had an experiernce w/this lens?

Abe's promises a 30 money back guarantee, but their reseller rating isn't that high - what to do???