Hi ,
I had to make the same decision a month ago. All in one unit vs build your own set up. I found the aesthetic beauty of a all in one ( Bio Cube type tank ) for me was a huge benefit . I went with the Aquapod 24, same thing though. It has all I need which I have learned is much of nothing at all. See , all I am going to use as filter media is the live rock in the tank along with live rock rubble in the rear compartment. I will have a heater back there , but that is it. No Bio balls, no filter sponges, no noodles, no nothing. I love the simplicity of this type of set up. I am adding Koralia water movers in the tank to keep water moving around. The lights on the tank will surfice most corals but your limited with a hooded tank unless it is metal halide lighting.
the Cons: more difficult to upgrade lighting, more difficult to add sump tank for added filteration, skimmer etc. Upgrades in size means you toss the whole tank and start over, being you wont have a standard hood, lights, sump,skimmer to use on next tank.
I love your choice though, have seen some beautiful Bio Cubes, and you can fill it up with corals w/o it costing a fortune. Good luck, I'm right behind you with my wife's Aquapod, should be filling with water within 2 weeks.