My experience with the Apex/Trident for the last 3 years:
Unit itself- Tests drift as the reagent goes down. So I just replace the reagents at 30%. No big deal. Cones do nothing for me. You can buy a 6 month supply (or a year). It feels like a chain around your ankle at first until you realize how often you were testing previously. It takes about a minute to change.
You can still run a test anytime you want.
It has helped me maintain a healthy SPS reef for 4+ years now with minimal effort. It is not perfect, Alk creeps up if I’m not paying attention since it auto doses and the reading skews as reagents go down, but I don’t have the time to test 1-2 times a day 7 days a week and when you account for user error with manual tests, it’s not any worse than your average hobbyist (that’s me).
The unit died on me and Neptune was helpful in troubleshooting (-including a phone call with a dedicated rep who took 30+ minutes to break down and reassemble the machine. That’s good customer service.
I’ll leave with this: after 10+ years now in this hobby and as a person who has purchased the cheapest equipment, upgraded, then upgraded again, tried every hack, workaround, fad, early tech, etc: This hobby is less about the numbers and more about the stability of those numbers. The Neptune Trident combined with other systems (like dosing pumps) will allow you to obtain the reasonable stability required to successfully maintain your tank and actually enjoy it. As someone who also has a Hydros system, I can tell you that my Apex has 99.9% uptime and I can load the app in Japan (10,000 miles away) and it is quick, responsive, and I can tweak things. I can not say the same for the Hydros.
It is not perfect. It is not the best auto-tester (and the tech is so new we are probably 5+ years away from an actual “good” one). But it will provide long term successful results with minimal effort.