We spent a total of 5 nights in Mykonos (2 nights in town and 3 at Apostolis windmills). Afterwards, we wished our entire stay was at the windmills.
The location is very close to a nice beach, within walking distance but we rode our ATV. The view is great, enjoyed meals on the patio overlooking the bay. It's far enough out of town that you'll need transportation or the bus if you want to go in town even though I think Mykonos town is overrated.
Kitchen and bathroom are very clean. Beds are comfy. Good wifi. The free transportation to and from the port was a bonus!
Only problem was we booked to stay in the windmill all 3 nights and they accidentally double booked so we were put in another studio apartment. Other that that we enjoyed our time and would recommend it. Very nice host!