[Question] What do all the different levels of microSD cards really mean for day to day use?

I am looking to replace my 64 gb SDXC extreme series card in my phone with a newer 128 gb model. I was just curious if anyone had experience with all the different performance levels in real life use.
 
Mostly important when taking pictures/recording video. For use as floppy-like storage it's pretty negligible.

--Patrick
 
Top