Definately a fan of having what I need so I can take care care of it myself. Roadside and AAA would be just a last resort backup plan for this sort of thing. Aside from not wanting a roadside assistance person touching my car you could be waiting for hours. No thanks.
I would never use the bumper jack on the GSX for multiple reasons. A lightweight portable jack in the trunk from the retail arm of the communist Chinese goverment wouldn't be a bad idea. And a 4 way wrench. Do they still sell those?
I keep mine in my trunk just for the hell of it but wouldn't ever use that bumper jack. AAA is a phonecall away.
I don't carry the stock bumper jack in my trunk, just the spare. I carry a bottle jack because it is compact and gets the job done. My only concern as far as spares go is that I have different size tires front (P255/60R-15), and rear (P275/60R-15). You can ruin a Posi rear if you put unequal size tires on. My solution is to carry a P235/70R-15 spare. It is 28" tall, the same as the P275/60R-15, and it will also fit on the front.