I just got my medium size cruiser case from LeatherLyke. www.hoese.com It's very proportional to the size of the bike and looks good. It mounts to backrest or rack, whichever you prefer. I left enough space between the bag and the backrest to be able to bungee or strap anything else I might need to carry on the seat. We put mine on the rack. It comes with 2 bars and you place them on the underside of the rack and drill 4 holes through the bottom of the case. We did change the bolts they sent though. The directions with it say that if you use it for a 'cooler' (yes, beer for those who indulge!), to be sure to wipe it dry and leave the lid open to air dry. It's close-cell foam which isn't supposed to absorb water. Hey, it locks, too. Very, very happy with the bag.