Yeah, I would definitely wait on the calcium checker. There has been a huge response to it's inaccuracy, so I believe they will upgrade it soon. And the phos checker is IMO a great ball park reader. If mine reads above 0.03 then I need to address something.
The more and more research I do on testing and test kits, the more I lose sleep. The truth is, what we are provided in the "hobby" is not top of the line. And unless you want to spend ungodly amounts of money, and then somehow figure out how to convert the readings, you will just have to have go by how your coral and fish look and act with the combo of what we are provided. All that said, hanna is doing a great job for us hobbyist, and I will continue to support them.