Has anyone put an after market exhaust on a V-Star 1300.  I have heard that it is quite difficult because of the fuel injection.  Stock exhaust has a nice quiet rumble, but it could be better.  Any ideas ?  

I've heard "BUB" pipes and "COBRA" pipes are the best for that bike.  

difficult to pipe a fuel-injected bike? no. more expensive? yes. but you don't have to buy a $400 power commander to get near stoichiometric optimum; your xvs13 will be perfectly happy with the cobra fi2000r, the dobeck techlusion, or the vance&hines fuelpak for half that price...which is still twice the price of a jet kit. but don't let efi put you off, and don't listen to anyone who tells you all you need is the pipes - that just makes the overlean factory settings worse. and don't forget to unstrangle the airbox when you're uncorking the exhaust!