if you planning on getting an APEX... better act fast. they have 10% off sale going on now at most retailers. I think the sale ends tonight though. I just picked one up.
I finally looked at some reefers signature line and it's reef angel, then I went to their website and liked all the add-ons. Seems similar to Apex so I'm wondering is this a T5 vs LED thing.
Also I heard thru the grapevine theres new Apex probes that test everything but you have to buy monthly refills of the cartridge.(more or less what I described)
Reef Angel is more customizable Apex is more user friendly (after you initially pull out all your hair). I have used both extensively.
Ha you won't like my answer - I have both.
I chose the Apex mainly because of Apex Fusion, how easy it was to setup and monitor my tank from anywhere. It web based so no waiting for apps for each platform and no need to open ports on your router to the outside.
I did some research and it had modules to work with equipment and brands I wanted to use.
I attached a screenshot of my fusion interface