We had a lovely time "living" at Guido's Ponte Vecchio apartment! The location was exactly as described...I even took a picture that looks exactly like Guido's sunny photo of the terrace. We were extremely comfortable, especially considering Guido has two air conditioning units for the hot summer months. This apartment is literally on top of an upscale shopping area - Salvatore Ferragamo and Dior are right downstairs. It's central location makes it very convenient for taking breaks from site-seeing when needed.
The only struggle we had was of our own doing. We brought along our two dogs, and failed to research dog parks in the area. The nearest park we found was about a 20 minute walk away. It wasn't too big of a deal for us because we enjoyed taking our dogs through the city - having to pass by the Ponte Vecchio and Uffizi several times a day isn't necessarily a bad thing!
As for Guido himself...he was a great host! He greeted us at the apartment and then guided us on foot to a nearby parking garage and made arrangements to store our vehicle safely for the duration of the trip.
We were very pleased with the entire experience and HIGHLY recommend that anyone visiting Florence make sure to book Guido's Ponte Vecchio apartment.