Pros:
Amazing location - on the southern side of the Arno away from the main bustle of tourists and near where actual Florentines stay. But a short walk across to the Ponte Vecchio, etc. etc. etc.
Clean - very clean.
Cons: reeeaaaallllyyy soft mattress. OK for a couple nights but if you like hard mattresses then be aware you might be better off leaving the bed as a sofa and putting the blankets on the floor.