Unless the spurs are hurting the hens, or a human for that matter then I would just leave them alone. They are part of the birds defence system. If you want to remove them then I prefer to use pliers and twist/pull them off. They come off quite easily with very little blood and whats left of the spur eventually rounds off into a blunt tip.
Interesting topic. One of my roosters has very long and sharp spurs. I don't think they're hurting the hens, so I probably will not remove them, but I'm wondering if it's possible to cut of the sharp point only.
I saw one this fall at an orchard who's spurs were so long he walked like those little wind-up toys: lift foot high enough to get left spur over right one - lift right foot high enough to get left spur over right one. If they got much longer, he would be hitting himself in the legs!
I have a short legged Japanese Bantam rooster and his spurs are poling him as he walks about. I tried to cut the ends off with dog nail clippers, but the spurs were so hard that the first cut broke the nail clippers!
I can not bring myself to try the 'twisting them off' method, so I am interested to know what else I can do.