Hi Zvika,
interesting question: for comparing two different distributions, JMP has a built in function called Life Distribution that can handle different groups of observations, as in the example from the documentation that you can find here: https://www.jmp.com/support/help/13-2/Examine_the_Same_Distribution_across_Groups.shtml#1326983
There is also the chance of comparing different life distributions according to different causes,as in this another example: https://www.jmp.com/support/help/13-2/Omit_Competing_Causes.shtml#1298294.
In our Mastering JMP webcast series there is also a recorded webcast on these topics:
Reliability Analysis for Non-Repairable Systems
However, what I suggest you is to submit your question as-is in the much broader JMP world wide community as a general discussion, so that it will be seen by other JMP reliability experst.
Cheers, Massimo