I am a fan of Magura, MT5's on one bike and MT7's on another, great stopping power, the only downside is with my big pig of a bike (125 lbs) I run a 224 mm front, 203 mm rear rotors and I boil the fluid if I hammer the brakes too hard, I turn the rotors blue almost to the mounting bolts, the...
I have had to push my bike for miles out of the mountains, sometimes down a ravine as pushing uphill was not a option, fortunately in the 2000+ miles I have logged on this bike it has been reliable, some of the failures were my fault not the bikes, overall I have faith in it getting me home.
It's good to see a dedicated emtb forum, ebikes are really growing and finally becoming more accepted, I have been on one for almost 10 years, now you find people treat you just like another bike for the most part. There are still the purist who make the grumpy comments on the trail, but...