I love having an apex, but yes it's basically a high end timer and thermometer. That said you can do cool things with it like control all your outlets around the thermometer if the tank gets too hot while they do sophisticated timer functions. For instance you can have two power heads occilate on/off either together or opposed from every second to every 999 minutes and shut off completely if the temp rises above 82.1 degrees. That program is at most 20 words, it's fairly simple IF this THEN that programming.
So yea it's a thermostat and a timer but so much more too. I expect Neptune to support the classic in a reasonable manner. For instance the trident Ca/Mg/Alk monitoring is not going to be supported on the classic I hear. This is in part due to the computing abilities of the classic not being capable of the programming required on the trident. Kind of like trying to play a 4K video on a tube TV... It's just not going to work. For this reason I would get the new version. I currently run a gold from a few years ago, and will continue to use it but eventually retire it to another use(sophisticated aquaculture timer) and upgrade to the new version in the next year or two. As of right now I travel 4 months a year up to 3 weeks at a time and without the apex and my ATO it would be possible but not so easy.