525 feels heavier due to gyro. Actual weight is about the same. Maint same, although more pain on oil changes and valves need to be checked more compared to WR, but WR uses bucket/shim on valves. WR valves usually never move though. 525 has lots of torque, 110mph+ fun.
I'd say KTM 525 is better for high speed riding, 450ktm + WR is better for slow tight ST. All are totally reliable