I recently upgraded my 517 to the Calvin Elite, and wish I had done it a lot sooner. It breaks so much cleaner, and even if you dont like the 8oz like I run mine at from factory, you got everything you need between it and 2.5lbs. There is NO CREEP, just a smooth break and bam.
And I spoke to a representative of OTM who shot the match that people had trouble with the CE because of the dust storm, but on the same day, people was replacing jewells with the old 40x triggers they had for spares because it was just that bad of conditions. Anything is capable of failing, Jewell isnt the God of triggers.
I have several friends who will be buying CE's now that I have mine, and they have tested it, with just as good of results with spending $50 less.