Started off using API, but changed over to Salifert and was pretty happy for quite a while. Then I tried Hanna for ph, and LOVED not having to interpret colors. Gradually switched over to Hanna for everything as the Salifert reagents ran out and continue to use them. Sure, the calcium and magnesium tests require a few extra steps, but after doing them a few times they’ve become easy. When the packets go on sale I’ll stock up a bit, but even at regular price I think they’re worth it.
Digital readouts rock!