Oops, just found this topic. So, Jumper says modifying skins is cheating? How interesting!
I wonder how people can even compare modified player model skins with modified maps. As Star already mentioned by giving the examples of Quake and Warsow games, it's legal there to use bright skins and by default in Quake you can change colors of the skins to whatever you like though modifying maps is not legal there and everywhere else because you have a different version of the environment which may help you to score flags faster, to see more or to get to some places to which naturally you can't get.
But what about skins in sauer?
By default you can find in sauer Inky models which are very bright and pretty big. So what kind of advantage we get by using bright Snouts, for example, which look as bright as Inky? Every newb who doesn't know about stuff like modifying player model skins can always use Inky and be happy.
So we have:
+ bright Inky by default for newbs
+ modifying colors of skins in the client of the popular game with which even developers compare our lovely sauer
+ bright skins can help you to get faster brain reaction but they can't help you to aim better or to see more than a player who use default skins