The Ajax is a nice hotel and had some refurbishment work completed during a winter closure. However, it is situated about a few streets back from the seafront whereas the Atlantica Oasis is just across the road from the sea.
If you can look on a map of the tourist area and find the Holiday Inn hotel, there is a road almost directly opposite (the fire station is on the same road, sorry - I don't know the name of the road off hand). Follow the road upwards until it meets Grivas Dighenis and you will see almost a continuation of the road you just followed from the seafront. The Ajax is about 200m further up on the right hand side. It's below the highway and in between Makedonias Ave and Grivas Dighenis street.
It is a nice hotel but possibly not so "holidayfied" (is there such a word) as those nearer to the seafront.
Regards