Most stores don't know much of anything about those guitars. Shoot, I walked into one and asked for a Jaguar trem bar, and they said "no, but we have a Jazzmaster trem bar"....as if there was a difference, I look at the bag with the bar in it and it said JAGUAR on it clear for all the world to see.
Went to another store, asked them if they had a Jaguar bridge. The guys literally could not remember the difference between a Jag-Stang, a Mustang, and a Jaguar, nor the difference between a TREMOLO and a BRIDGE! They bring up a Mustang and a JAguar tailpiece, and I'm thinking "goody". Then they asked what style I play, I say Metal, then booger hands me a licenced Floyd Rose...WTF!?!? No way in heck I'm replacing the Jag trem with one of those pieces of junk, I don't have to unlock the nut or cut strings up to install them, and it stays in tune all the same.
My Jaguar came with a MUSTANG tremelo bar too. Bonus is I have a spare for My Jag-Stang, and if not, I have one for when/if I decide to piece togeher a custom Mustang.
Either way, the Jag is an excellent guitar, it's just all in the set up. Heck, I use one for metal without any real changes, and it's been the most stable axe I've owned.