I have tried the cheap ones and they are terrible off road.There is nothing wrong with the cheapest hydro shimano ones for the cash
Cheap Shimano brakes are awesome – just if you swap the OEM pads which you’ll destroy in a ride or two in the right (or should that be wrong?) conditions – Fibrax sintered ones are very good.
My Shimano 525s from my ’05 Stumpjumper are still going strong. they’ve done the Alps and most UK trail centres. Never overheated (I’m not light and dragged the brakes a LOT in the Alps AND had sintered pads in). They’ve been faultless. I’ve only bled them once (althought they need doing again TBH). I want to build a new bike up in the new year and the only things I’m definitely keeping from my current bike are the Fox Vanillas and my bog standard brakes.