You can somewhat control the bandwith by limiting the number of simultaneous peers: in my case the usage seems to be around 5 Mbps up/down.

If you're running it from home, the real problem is not the bandwidth but the number of open connections the router has to keep track (assuming the network is NATed). The default settings will likely crash any cheap consumer router, so I would run the daemon from a VPS or a machine that isn't behind a NAT.