Buwizz torque

Looking to invest in some motors & a controller (have none sofar) & have been reading advice on here about PF/PU -vs- 3rd party - I've repeatedly seen it said that BuWizz is by far the "most powerful" but haven't found any data on what that means. Browsing YouTube I've seen conflicting info - BuWizz seems mainly used for speed, some folk implying PF/PU might have higher torque. Obviously you can gear these things down to get different results but I'm interested in what the motors do out of...