This may not be accurate, but it appears that most people who go with Gas-N pipes choose the Touring (quieter) version. A complete guess based on what I read.

For those of you with the Gas-N standard pipes, any regrets? Do you still like the sound and volume (two different things)? Mention your engine because that makes a difference.

I know this is a completely subjective question, and I've seen the good video comparison of the standard vs touring pipes.