I own a GS1000G and thought about putting on the Vance/Hines and the Mac, but after viewing them on other machines I don't like (my preference only) the way they sit really low to the ground.
I looked around for a Alpha system but couldn't get hold of one (I used to have one on my GS1000G when I was 19)
I decided to go ahead and get a 4-1 Harris system, I had to have it shipped from England, but I must say the chrome finish is wonderful.
I have a friend in England that rides a Kawasaki Z1000ST with a Harris which sounds great, with no power loss and no real loud behind him.
I have not even started mine yet, but will post a little note when it's done.
If you do decide to go get a 4-1 pipe for any model, DONT buy the MOTAD system! it's crap and restricts any machine.

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