From someone who has been there and done the Tredwear thing, don't do it unless you're 100% sure of the lettering and 100% sure you're never ever ever ever going to take them off again. Also be prepared for them to look grubby after 100 miles and then never regain their shine no matter what you do.
They do look cool though, I must admit. Well, dependant on what they actually say of course.