Airplane battery: Freedom V2 vs Medistrom opinions?

Twice in the coming months I'll need to use CPAP on an international overnight flight, something I've never done before. I have an AirSense AutoSet 10. Both planes claim to have an outlet at the seat, but reading fine print it explicitly states on two different airlines that I need to use a battery for CPAP machine and cannot power it off the seat outlet. I want a battery anyways in case seat outlet doesn't actually exist or is broken.

Does anyone have an opinion Freedom V2 vs Medistrom? Both seem to provide passthrough power for home use in case of a power outage, which is a nice benefit for use when not flying. Freedom V2 has more capacity according to teardown video below, and comes with more adapters for different machines. Medistrom is more compact, works only with AirMini & AirSense 10 out of the box - you need to purchase adapters for other machines. Freedom V2 says they are TSA approved by being 99.9 watt hours (it has to be under 100) but teardown indicates otherwise. I don't know if they've somehow capped capacity through other methods. Medistrom is 24v only (separate 12V model), Freedom V2 battery can output 12V or 24V if in the future I have some CPAP machine that runs on 12V, or another 12v device. My main concern is reliability, support.

Link below starts video right at point of Freedom V2 teardown:

https://www.youtube.com/watch?v=ONVmcuXWP8E&t=992s

I'm leaning toward Medistrom since its more compact. Longest overnight segment of flight on my trips is 8 hours. Any other alternatives I am missing? I'd love to get a TalentCell battery for <$70, but the 24V supply is unregulated so there are reviews saying sometimes CPAP won't start when battery is fully charged, since fully charged the output is closer to 28V. Same with as the battery drains, it could dip as low as 22V. I don't want to damage the CPAP while travelling without access to spare machine, so I'd like to use a regulated 24V supply.

I also have the dummy "plug" for the AirSense 10 to remove the humidifier tank, making the CPAP machine itself more compact.

Hmm, I wonder if Medistrom is still in business - I noticed their website disappeared: http://medistrom.com/

Freedom v2 seems made by an outfit "cpaphero": https://cpaphero.com/freedom-v2-battery/

EDIT: I was able to call Medistrom and get a hold of someone, seems their website is down as is their parent company http://choiceonemedical.com

2nd EDIT: two days later, both websites are back up!

The Freedom V2 battery might not be a regulated 24V output either, which is the same issue as the TalentCell. Quote from manual:

Battery Starts Then Stops Working
If the battery starts powering your device and then shuts down, try to
reset the internal circuitry (see page 5). If the battery continues to shut
down, the device you are trying to power may:
■ have higher amp requirements(> 8A) than the battery can provide
■ require a constant voltage output to operate properly (the Freedom
V2 battery operates on a voltage range of 10V-28V)

Manual link copied from cpap.com listing: https://646c480ddc37fd8605e3-4898386040 ... manual.pdf

My V2s lasted a bit longer than the year long warranty period. No help from support. Recycled.

Freedom V2 says they are TSA approved by being 99.9 watt hours (it has to be under 100) but teardown indicates otherwise.

TSA actually allows batteries of up to 160 watts to be carried on, but individual airlines might not allow batteries that large. See here under "Lithium batteries with more than 100 watt hours":

https://www.tsa.gov/travel/security-scr ... ibring/all

I confirmed via email with cpaphero that the Freedom V2 it is NOT a 24v regulated supply, so I went with the medistrom whose support team says it is. I'm guessing thats why medistrom sells separate 12V and 24V models. I'll check with my multimeter once I get it!

The freedom v2 seems no different than the far cheaper TalentCell in terms of the output voltages it provides. The model below is 82.88Wh - they offer models with larger capacity for not much more money - I was looking at this one due to it being under the 100 Wh limit to fly with it without having to notify airline / get approval:

https://talentcell.com/lithium-ion-batt ... 240a1.html

Its $62 on Amazon. TalentCell sells this cable to connect the AIrSense 10: https://talentcell.com/power-cord/24v/2 ... -cord.html which is on Amazon for $10.