im interested in seeing some of your projects. are any of the youtube vids your layout? hey, if you ever need prototype pix and are looking for a particular kind of era, car, artist or whatever let me know. I have been shooting graffiti on trains since 1986.
I can understand the argument that grafitti is, sadly, a fact of life in many cities both in the US, Canada and here in the UK and that in the cause of accuracy, there is a legitimacy in reproducing it on models. Fine, do so if it represents the area and era you are modelling. When you reproduce your "authentic" grafitti, just remember how pleased the genetic mutant half wit, who vandalised railway property, will be to see his "tag" represented on your model railway.