Holiday Inn has the same problem. And there is no one train that will take you to where you probably want to go to be in the tourist mix at either the Pantheon or Piazza Navona. You'd have to take two trains or trams, or a tram, then walk to a bus station, and take a bus, plus close to a half a mile walking. That's why it takes at least an hour. I don't know if the Holiday Inn has a shuttle like the Sheraton does, but having to take a shuttle is a deal breaker to me. They are a waste of time and only run for limited hours.

Depending on how intense your meetings at the Sheraton will be, and depending on whether or not you've ever been to Rome before, I'd stay in Rome and travel out to the Sheraton, rather than the other way around, unless your meetings will last into the evening and you'l have to hunker down in your hotel at night to do work for the next day. On the other hand, if your meetings begin at 9AM, are relaxed, and end at 4-5 (as is usually the case in Italy) and you have an opportunity and desire to explore Rome and to do things there, then staying in the city is and traveling out to the suburbs for business is better, at least for me.