There is no such thing as a one for all RF product that works 100% in all venues.
I've had great luck with Axient, but YMMV. It'll tune across all the available bandwidth in the US and the closest to that statement being true.
Nothing ever works 100% of the time, agreed there!
I like to think I'm worth my salt, and have certainly toured with lots of A list acts that have people with many more grains than I do. We all have carried RF in our trucks as waiting for show-stopping deliveries from VER (with potential for for non working set ups or incomplete pulls) isn't in the cards. The racks are built and tested at Sound Image or Clair or SES and yes we have a plan going into all areas, however I still have yet to see any major production rent RF on a gig to gig basis, minus one offs, fly dates, and broadcast/corporate gigs.
Anyway, for the amount of gear the OP is asking about I doubt any of this comes into play. I'd be a fan of renting for the entire run. Also definitely can recommend the Shure rechargeables, They've been awesome over a few years in the Axient, ULXD, and PSM1000 rigs I've toured with. I wanted to hate rechargeable batteries based on older nicad offerings but they have been rock solid.
JF