I was thinking just this the other day, good question! I really like the Jazzmasters, the way they look, feel and play (when set up properly at least, lots of bad Jag/JM set ups in stores!) but they've never quite had the tone for me.... very good but not quite there. If something bigger, ballsier with a round and articulate tone was available I could well see myself picking up a JM and putting them in. One of my favourite bands, Bush, have had some great Jazzmaster tone over the years, good stuff.
N.