Ciao Darren,
Both are good bases but are pretty far south in Tuscany - so whether they are the best totally depends on your planned itinerary for the 10 days. What places in particular are you planning to visit? Maybe a more central location in Tuscany, north of or around Siena, would be more ideal in general. That way Cinque Terre is also closer.... and I'd put Rome at the end of the trip, if that's where you fly out from, moving down there so that you don't have to drive back up.
If you have a planned itinerary in Tuscany, share it with us so that we can give you more specific suggestions of other places to consider as a base for your vacation! Have fun planning

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