And AK as well.
I had this done to a couple other AR bolts and have never regretted it.
My M&P-15 BCG is going in this time. Cleanup is a breeze and it makes/eliminates any form of problems going into battery (with the exception of an obstruction).
DISCLOSURE: I do not work for them or have any financial dealings with them other than as a happy customer.
I love robar too.. my Px4 is with them right now and I have sent several FCG there.
Can you post some picture of your Robar bolts for scuffs and any possible discoloration?
Id like to see how they hold up.