We really enjoyed our stay at Elements 108! The location is perfect: right on the beach, and a very short walk up to the main drag (5th Avenue) and the many shops and restaurants there, but still far enough away to avoid all of the late-night noise and partying that you would hear if you were staying right on 5th Ave. For some less touristy food options, you can walk just a few blocks up Avenue C.T.M. from the condo: there is an amazing breakfast/lunch/juice bar place, as well as some awesome taco stands! We prepared quite a bit of our own food, and it was about a 25 minute walk or ~$5 USD cab ride to the Mega or Walmart for groceries.
The building and grounds at The Elements are terrific, and we especially enjoyed the large pool (including two different depths of children's pools). There were nearly always available chairs around the pool and at the beach, which was a very nice change from staying at a resort. The condo unit itself was also awesome; wonderful bedrooms, beds, and bathrooms, plenty of space and storage space, a terrific deck/patio, and a nice living and dining room area for everyone to enjoy. The in-unit laundry is also amazing when traveling with kids! Matt was wonderful enough to obtain two pack-and-play cribs for us to rent for our twin toddlers to sleep in.
A few relatively minor drawbacks: 1) The dishwasher does not really clean the dishes, so we ended up just doing dishes by hand and using the dishwasher as a drying rack. 2) There seemed to be a lot of construction going on, making it rather loud and unpleasant to sit out on the lovely patio during the day for much of our stay (though this would of course vary, depending on when you visit). 3) The beach area in front of the condo is near a marina, so the smell of gasoline sometimes drifted over to where we were sitting on the beach.
Overall though, this was a fabulous rental, Matt was wonderfully prompt and responsive in our communications, and we would absolutely stay here again if we return to Playa del Carmen!