You're gonna get a bunch of different answers on this one. I put S/E II slip-ons on my 05 sporty and love the sound. Did the dealership give you a gift card or any kind of free-bees when you bought the bike, you could use that towards some slip-ons if they did. Who did you buy your bike from? I bought mine fron Manatee River down in Bradenton and really like that dealership,I'll buy my next from them most likely

By the way, you shouldn't have to recalibrate yous EFI system with the addition of the slip-ons. Welcome to the forum!