IS THERE A BETTER TEST KIT

I've been using Aquarium Pharmaceuticals test kit to measure the Ammonia,
Nitrites, Nitrates pH ect.. After taking the prescribed measure of water and
using their solution, and waiting the appropriate amount of time, you
compare it to the color strip cards they provide to the color of the test
tube. I've been told by various people that you compare the color of the
tube to that on the cards, you should hold the tube up to the light and
compare that color to the color on the card. Others have told me to place
the tube directly on the card to compare the colors. You get dramatic
differences in the reading depending on what way you do it.
I always get readings between the colors and I can never tell what I truly
have. Is there a better way to test the levels in my tank? Also what the
correct way to measure the colors against the cards.

Thanks