Tourist trap full of junk you don't want. This is the same stuff (junky football jerseys and t-shirts} you see all over bigger cities in Italy (around the Duomo, along Strada Nuova...). Even the three teens in our group thought it was awful. And that was on a day when it wasn't even crowded with tourists.
Far better to go and get gelato at Gelateria Santa Trinita and wander around the Oltrarno to buy stuff from actual artisans.
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