EML, we found that on 16" sidecar wheels which have the bearings more exposed to the elements that SKF had the better seals to seal out the muck and water. Other brands such has NTN had crap seals and needed replacing after 1 wet muddy event. Then changed to SKF and they have lasted several years/several seasons. The seals are just so much better at at sealing out the mud, dirt, water and you can actually see the seals are better quality and a tighter fit.