they are atleast as strong, the yamaha ones pull a little easier than the ones i have,
yamaha used steel zink plated, or steel with a anodized brown. viper ones are steel. after i buffed mine a few times the edges of the rivots where the zink wore off would rust.
thats why i say, if your going to do a new polish, the best result will come from taking all rivots off, then sand with 2000, buff, polish then install rivots.