My feeling is that strips are harder to read than liquid tests. So, from my PoV that makes liquid tests more accurate than strips because you are more likely to read them correctly. I use both, strips if i just want a quick check, liquid test if i actually want to know my water parameters.
When i do a test with both, i don't find differences in the readings, but there is more ambiguity with strips.
Liquid test kits are also more cost effective than strips as you get 100s of tests out of them.
API master test kit is commonly used, covers the basics and is considered reliable.