I hate all testing, and I love the trident. Testing is filled with so many pitfalls from user error to big +/- . Comparing tests is nutty because how do you know what is rightest? All you can really hope for is ballpark trends, which can be really useful. The trident, and the apex, give you awesome trends. And the trident has been holding up to the testing we do at CAS - though I still don’t know which is rightest, but they are similar.
At home I use api all tests because it is simple and puts me in the ballpark. For salinity I am still deciding what I like (currently running a long term thing - the Misco is currently winning, but is 500 bucks with the lowest +/- and you calibrate with every use). For phosphate and nitrate I use a Hach dr890 and do the tests exactly the same way as much as I can. For all other tests, I generally use aquamedicwatertesting as they have almost always been comparable to the lab tests CAS, and they do the tests the same way every time with auto titrators/colorimiters to take out some human error - plus they use up to date reagents and calibrations (something that can be problematic for home testers). I also don’t see color well so titrations have always been frustrating.
The trident, testing all 4 times a day give me a lot of confidence in the trend. Twice a day for Mg and Ca give good trends as well. And, as I say, the results have been well in the ballpark of tests I have been able to trust over time.
I have not had the time or funds to set up repeatable testing of hobby test kits with certified standards, so I have no idea of how in the ball park popular test kits may be, but the +/- on some is large.
Trends are your friend. One off tests for specific numbers are not your friend. Trident is amazing for trends.