yeah they protect it well. im not sure if you can get aromodillo type ones with metal in though :rolleyes: i would think it would still dent the frame because the meatal would not callapse like the plastic and just dent into the frame :S
it won't be too much im getting my rims grinded this weekend at my local bike shop, i think its about £10 for both if you only take the in the rims. :)