As far as I know, Apple iPad doesn't support FictionBook FB2. You need install additional app to read / open FictionBook FB2 files on your iPad. Not sure if that's possible at this moment because I don't have one.
Now, if you ask me about peripherals, iPad is not one of the best, they don't have USB ports, for example. There are other tablets which much more ports and way to get access. I do have a Galaxy Tab with full Android Market access. Downloading an app which supports that format and uploading via USB would be extremely easy, even downloading directly from Internet. My 2 cents.
I'm afraid I can't make additional comments on iPad because I don't own one.