I would echo what @codymanhas said above. In terms of ruggedness and cost I don't think you can beat the Countryman B3.
That said, I personally don't enjoy the sound of them as much, but I think that is more a case of familiarity listening to Sanken's and DPA's the majority of the time. After some post EQ and sweetening they will get you there.
My understanding of the SMWB/SMDWB is that the transmission power no longer effects run time on the wide-band transmitters.
The transmission power is attenuated before the antennae, but the transmitter itself isn't running at variable power, per se.
If you are connecting directly to a recorder/RX in a non-SMBus configuration you only require the 2 wire/conductor battery cup.
Jose Frias compiled an incredibly comprehensive source a few years ago.
https://chapterfour.com/blog/technology/power/smart-battery-shopping-guide/
I'll second what Trey said above. Go for the Audioroot battery cup and charger I may add. I'm over a year into using it along with Hi-Q batteries, 100% satisfied.
Sennheiser releases statement on FCC frequency spectrum ruling.
http://www.prosoundweb.com/channels/av/sennheiser-releases-statement-on-fcc-frequency-spectrum-ruling/
During scenes involving talking to screaming or loud transients, especially while OMBing, I'm a big fan of having an XLR(F)-2XLR(M) splitter & gaining the second channel conservatively, by a good 6db or more.
I would also like to extend my thanks to Tyler Wade. Tyler was always great to deal with. I had many interesting conversations with him at the shop over the last few years. I was recently enjoying listening to him host the new Trew podcasts. Sorry to him go, all the best to you good sir!