I own all six officially released Apple leather cases for the iPhone 11 Pro Max, and protection is no problem at all.
Well yeah, it’s an investment, but it has kinda become a hobby, and it gives my phone different looks for different occasions. But, unlike the Apple Watch bands (which fits every model of the watch so far), it feels a little wasted when I sell my phone.. oh well..
About the yellow case, it sure is looking good, but I would be careful if you are mainly wearing dark blue (heavy dyed) jeans, as I believe it could stain the case. But except from that, I love the bright yellow color.