Depending on the number and kind of seeders I would say that I can download a “normal” movie (2-3 GB) in arround 4-12 hours (sorry that i dont have some real numbers, I could check again later for that). So you probably won’t be able to say “hey, i just saw this new i2p-torrent, lets quickly download it” but its defenitly usable, especially when building a library. The “worst” torrent I downloaded was like 50 GB of House M.D. that was seeded by just a single person, but after roughly 1,5 -2 Weeks it was done!