I've been undecided on which controller to get since bowing out of the Vertex Cerebra beta group last year (crazy delays after purchase), but have finally decided on the new Apex. At first, my thoughts were to pickup a Classic or JR preowned and just add-on modules/probes, but the cost savings honestly didn't seem worth it. To get things the way I'd like them, it would most likely cost me somewhere in the ~$600 range and I'd rather just pay the extra $200 and have a new setup. Another big selling point for me is not having to hook up a bunch of modules, since the 4 primary monitoring aspects are built-in, not to mention not needing a WIFI bridge. Lastly, I see the upcoming Trident as an absolute game-changer and this won't work on the Classic model, so that pushed me across the decision finish line.
I've been in the hobby since 2001 mostly with 120+ gallon systems, but have switched over to the nano side of things in recent years to coincide with lack of time for maintaining a large reef. I realize not many people run a full-blown controller setup on a 14 gallon tank, but that's where I'd like to leverage technology and automation to keep my parameters as stable as possible and really push the smaller footprint to it's absolute limits. As important as that stuff is in a large system, the swings can be much quicker and costlier (tank health wise) in the nano realm, so I really want to invest in a top shelf system and for my specific situation, I feel like the new Apex combined with the Dos and eventually the Trident will bring me to the control I want.