Originally Posted by AnthonyG
I'm training and racing on Sora hubs at the moment and they work flawlessly. I repacked them from new and when you spin them you feel just a slight amount of roughness but honestly I don't feel that they're holding me back at all. Shimano quality is top rate and being Shimano they are loose ball bearing hubs which is fine in my book.
Regards, Anthony
Might those be adjusted a little too tight then? I'm not saying you don't know how, but just in case, make sure the hubs have axle play prior to QR tightening. The QR should just barely remove the axle play. When the hub is off the bike, it should feel silky smooth.