This is not a 'affordable' product. One doesn't buy it lightly. But a while ago I bought a tool from a well-known cheap Chinese site, to see whether I would/could use it: it came with a cm divided in 8 (!) mm's), and a cheap feeler gauge from a DIY-store was so greasy I didn't want to expose my strings ans fretboard to it. So I decided to go upmarket and buy a decent set.
Sadly I was disappointed. I ordered it new, but it felt like B- or even C-stock. The string height gauge had a big fat oily/greasy stain on it, like someone eating fish & chips with his hands had put it in the case. The yellow feeler gauge was scratched and had a black curly pubic hair stuck in it, that was hard to remove. The parts weren't snug in the case, some fell out spontaneously when opening it. Still, the box containing the case showed no signs of being opened before.
The yellow gauge (the main reason I bought it, next to Phil McKnight recommendation of the string height gauge) also is so tight it is hardly workable. On a technical level: where many luthiers in YT-videos use feeler gauges to measure the string height, this set (the yellow one) does not strictly measure the string height, but mainly whether it is too high or too low. You can't replicate their method.
One can imagine the state this set came in is not inviting to work with, so it mainly lays around waiting until I find the courage to clean it up.
Potentially a good product, but apparently I literally had a bad case.