Did this the other day because i realised that the 550ml Ti pot that comes with the Ti Caldera cone is of a very similar diameter to the JetBoil.
It works but not as fast as the original Ti pot except that I can boil up to 1 quart in it, (not that I would...) or cook a meal rather than just boil water and re-hydrate separately as I do.
Although a bit slower than a standard pot with the CC, it seems ( if left on the cone) to retain heat better than my Ti pot, provably better than a standard aluminium one too.
Not if you are looking at weight savings nor speed. Great if you happen to have the two in the first place and a personal finance minister (AKA "wife" )
Franco