For a reef tank I really do recommend salifert - the three that you would really only need more than what you have for they cycle are calcium, alk, and mag, well, their high/low range nitrate test is a good one to have too. Their ph test is just like any other though, with a regent you put in a vial of water and hold it up to a color chart so nothing special about theirs. They are a bit pricey but are both accurate and precise. I did different tests with them to see how well they work, testing calcium and alk - measured out some RODI water and dosing in B-ionic two part, raised the calcium and alk in levels, testing with the salifert test kits each time, and they were always spot on, down to their lowest step - I think 5ppm, one drop of test solution.
I had also tested my tank water multiple times in a row to see if I would get the same reading, and I did get the same reading each time. Would dose my tank with how much b-ionic would be to raise the calcium 10ppm, and then tested the water, and it tested exactly 10ppm higher.
They cost more but I know I could trust the results.