Very nice modern rooms and welcoming on-site staff to help with any needs or suggestions. Large walk-in shower was a plus. The hill is nice for views and sunsets, but can be a bit of a 2-3 min cardio workout if you return to the room on foot a few times a day (obviously not a problem if you rent a vehicle or go by taxi). Large, free parking lot for guests to use too.
For me, Eternal was a good mix of hotel and lite-studio, while being right on the edge of Mykonos Town with easy access to both the Town and the rest of the island.
If possible, try and request an upstairs unit as my unit was on the bottom row and could get a little noisy on Friday & Saturday (but it is Mykonos after all).
I would stay again.