In 2005 before the devaluation of SPG points we stayed 3 nights in the Florence Westin Excelsior in a terrace room - not a suite but a beautiful room with superior woodwork, padded cloth wallpaper, and an incredible view of the Arno from the very large terrace. The points per night was 14,000 ... the room rate was 1400euros. We all know how much that has changed now.
For 300 euros, take advantage of it - that's a super deal - and earn more points and perhaps a free night.
We went over to the Grand for a looksee. It seemed much more modern than the Excelsior, and smaller, but equally classy in its own way.