straight pipes wont pass inspections in most places.. so i probably wouldnt recommend that.. plus i dont think it would sound that great on a VX anyway..

I would go the route of a simple straight through glasspack muffler, i have heard good things about the magnaflow 18" version w/ 2-1/2 in and out. Its similar to the powervault and powervault 2, just different size i guess.. here is a sound clip of mine (powervault 2)
http://www.youtube.com/watch?v=5FX3A4Wc8QQ