More pedal does not need one

I have currently installed on 2 wheels MTB clipless pedals. The offered here really cheap 520ger from Shimano and a significantly more costly end XT, also from Shimano. Visually they look except for "XT" logo for the layman alike. Allegedly, the bearing at the XT somewhat high and the metal alloys the XT would be easier. No Matter. Both defy any weather for 3 years and get only from time to time a pack of fat camp and a little oil on the feathers. The each have thousands of kilometers behind him, but no trigger mechanism of the 4 pedals ever clamped. Everything still works like new, despite a few scratches due to contact with stones and the roadway. The bearings rotate as fresh from the factory. Whether 520 or XT. With a balance I might measure a few grams difference between the cost and the significantly more expensive 520ger XT, but clicked I see no difference. I dare say: no one notices the. The forms can be a maximum. Maybe I see in the distance differences in durability that can not yet be now guessed. I do not believe it. Conclusion: 2 in my eyes are the 520ger and the much more expensive XT absolutely excellent pedals. At least for higher quality or performance but I would not buy expensive XT more. The 520ger hands me 100%.