We enjoyed our holiday in Naxos last week (August 2014) but we had a bad experience with Moto Falcon.
We hired a scooter and a quad bike from them for 2 days. My scooter proved to be faulty - it could not be started via the hand electric starter and I had to use the kick-start. I took the scooter back but Moto Falcon were unable to provide me with a replacement at the time. The scooter got increasingly difficult to start, even via the kick-start with the result that I had to push it back to the shop.
My husband was charged for damage to the quad bike parking brake which he was not aware of while using the bike.
The staff were rude to us on the return of the bikes. We had been careful to use the bikes properly and had taken out the full insurance.
We then hired bikes from another bike hire on Naxos who were friendly and helpful.