In the past I used other P2P sharing, the German O&O File Direct, very similar to this. Worked fine but sadly only freeware and only for Windows. This system is obviously the best way to share files, the only disadvantage is that the sender's PC must be turned on and online, so that the recipient can download the file, but on the other hand it also gives full control over the downloads, which because of this they can be interrupted at any time, simply by going offline. Currently I use Wormhole