I think I've mentioned this somewhere before, but the buzzstop has more effect on the feel of a guitar than the sound. It puts the strings under a little more tension, and changes the string angle over the bridge, keeping them from slipping out of their saddle grooves so easily. The Mustang bridge, however has, in my opinion, a very noticible effect on tone, increasing sustain and adding a little more midrange harmonic content. This is probably because the saddles have more mass, and there are fewer "moving parts" to loose vibrational energy between. Also, because Mustang saddles lack those wobbly hight-adjustment screws, and they're bigger than the usual Jaguar saddles, there's more contact/coupling between the strings and the body, increasing resonance, in general.
