It looks like an older version of the skimmer that´s now is the Coral Box series. I run a Coral Box 500 + in a 80 gallon system and are very satisfied with this skimmer. Its a little bit sensitive for "dirt" in the intake and at the needle wheel - you will hear if you have problems with that. If its happen - just clean it. The + serie has level watch in the skimmer cup and shot down the skimmer if its to much skimmate. I run my skimmer very dry because I want to have as good gas exchange as possible. Its easy to adjust the level in the skimmer (with the outlet valve) and run the pump with max speed, hence a lot of air into the skimmer.
The 300 + should probably be a good chose for you
Sincerely Lasse