First off, I have an APEX and it 'gets the job done and has done everything I wanted it to.' Second, I am a programmer by trade and I REALLY like the flexibility that the reefangel gives you coding wise. If you are just going to be doing the 'typical' stuff like letting it control your lights, control your heater, turn on/off this, etc, the APEX is probably the easier of the two to set up. On the other hand, if you want to do some custom coding (like programming 'reef crest' mode for your jebao wp25/40 pumps, very fast lightning storms for your diy led lights, etc) then the reefangel is easier to work with, imo (from looking at the examples on the reefangel website). Doing the latter gets rather cumbersome with the APEX as you may have to create several virtual outlets on the APEX and it is just a 'different way of thinking' than I am used to when writing standard 'code' like the reefangel uses (a simple if/else statement would suffice in the regular programming world...).
Again, with that said, I believe the APEX is the easiest 'plug and play' solution and is rock solid for the typical aquarist.