Those Skypephones from 3 are quite outdated and had a relatively short battery life. In your place I would buy a recent E- oder N-series Nokia phone (e.g. a Nokia E52), which supports VoIP, get
a free VoIP account including free geographical US-number from sipgate.us and so you would be reachable free of charge on a regular US-number in Italy. People could call you using regular phones instead of computers or Skype-capable phones and they will of course pay only a domestic call, while you won't be charged for receiving those calls at all. Of course you can also place outgoing calls to the US at
sipgate's rates, which are quite low.
Just make sure the Nokia, you chose supports SIP (the required VoIP-protocol) and both, HSDPA and HSUPA, as the lastmentioned will reduce latency and so there won't be a lag in your calls.
P.S.: You might need someone in the US to sign up for sipgate.us as they might restrict registration to American IP-addresses. However you'll be able to use the VoIP-account even from abroad afterwards.