As for the test kit, it may be better, but I still don't like it lol. To much room for error. "Put drops in till the water turns yellow" what kind of yellow? My yellow and your yellow may be two different things.
What you have is for measureing GH (general hardness) and KH (carbonate hardness). Neither test is really necessary unless you are keeping specific plants or breeding fish that need soft water.
The instructions are very clear and accurate for what they do.
You are looking for a
color change, so the 'shade' of your new color (green for GH, yellow for KH) does mot matter. It is just the number of drops needed to cause the color change which gives you your value for GH or KH. But, GH and KH results are not really important to the majority of aquarium owners.
The same manufacturer makes tests for ammonia, nitrite and nitrate (along with low and high pH tests) that are more helpful for the fish keeper.
Besides, I'm lazy... Lol.
So if you had the testing ability for ammonia, nitrite and nitrate, you would be too lazy to use them?