"Cyclists can be a fickle bunch, preoccupied with the latest flashy advances. But while marquee products get all the attention and column inches, that’s not what most people are riding. It’s the workhorses of a brand’s product line-up that are out there in multitudes, not because they’re the best and the most expensive but because they’re perfectly fine and the right price."
The PD-M520 is really a perfect product in my estimation. Affordable, dead reliable, and built for the long haul. I'm glad I bought a set of these with my first nice bike - and I'm still running the same set to this day, never needing a bit of maintenance.