In my experience with the GH6, the battery life is definitely the biggest hurdle for long-form stuff. If youre doing a music doc in Seattle, you are gonna be stuck in dark venues with no easy access to outlets. I've tried many setups over the years, and honestly, a bunch of spare batteries is just a recipe for missing a key moment while you are fumbling with the battery door in the dark. I strongly recommend grabbing the SmallRig GH6 Black Mamba Cage as your base and then mounting a V-mount plate. Something like the SmallRig VB99 Pro V-Mount Battery will keep you running for hours without worrying. It adds weight, but the reliability is worth it. As for the cards, its a bit of a toss up depending on your settings. If you want to shoot the high bitrate ProRes stuff, you absolutely need a CFexpress card like the Lexar Professional CFexpress Type B 128GB Diamond Series. I have seen people try to skate by with the SanDisk Extreme Pro 128GB V90 SDXC cards, and while they work for most 10-bit modes, they can occasionally choke if the buffer fills up. For a doc where you cant ask for a second take, go with the Type B for your main slot. The peace of mind is worth the extra cash. Better to be safe than sorry when youre on a tight schedule...

Just seeing this now. For a music doc, you gotta weigh speed vs cost. Ive used both and honestly:

• ProGrade Digital SDXC UHS-II V90 256GB is plenty for most 4K stuff unless youre shooting ProRes 5.7K.
• SmallRig GH6 Full Cage 3784 is a solid, cheaper alternative to other cages.
• Anker 737 Power Bank 24K via USB-C PD is a lifesaver for long sets... kinda better than carrying ten batteries. Check the official Lumix compatibility list on their site to be safe.

Interested in this too

Wow ok that changes things. Gonna have to rethink my approach now.