Will be going to Rome later this month.

Any particular brand of prepaid SIM stand out?

Would obviously want to call and get calls from the US.

Preferably something I can pick up at any store, compared to something like the Riiing SIM which apparently clears your credit card charge through some Chinese bank.

I've seen the TIM SIM but is there any better? According to telestial.com, calling the US is 50 euro cents, which is only slightly better than if I used the T-Mobile Prepaid To Go plan, which charges 99 cents per min to call back from Europe.

Also, is a multi-country SIM a better option? If the air time doesn't expire, it might serve for later trips to Europe...

I have a two hour layover in CDG so if there's something I could pick up at the airport.