I have years of experience in asm programming with PIC processors, and my job is embedded software development. I got an STM32 development board a couple years ago to get my feet wet in ARM embedded development. I got completely bogged-down in setting up the development environment. It took me forever to get a blinking LED, and I spent an ungodly amount of time unsuccessfully trying to figure out how to change the rate based on a potentiometer input.
It was a very frustrating experience, but articles like this make me want to dive in and try again!