I have one and have also ended up with a bath-in-a-change table thing so i'm not sure how useful it will be. I haven't used it yet
After bathing Alex at the hospital i think it's probably a bit impractical size-wise (and as the other mums have said, looks like they'll grow out of it pretty quick) - but it's probable good for when you start out because at least if they have a strop you have the hammock there!
Personally, i now think i wouldn't have bought it (and ive only bathed DS three times) because as long as your confident with your baby you really wont need the hammock! Just my personal opinion though!
Good luck!