Difference in battery life between MDR-ZX550BN and BTN200?

Question

I am looking to buy either the MDR-ZX500BN or the BTN200. There are, however, some information that I can not seem to find or get confirmed anywhere. Therfore I hope that it can be sorted out here.
The differences that I can find (correct me if I am wrong) with the newer MDR-ZX500BN are:
- Texture (material?) on the earcups and hinges have switched (metalic and platic)
- Noice canellation (90%)
- Minor changes in button layout (button for anwsering calls)
- 10 grams heavier.
Another thing I noticed is how it claims a battery life that support up to 25 hours of music playback, while the older BTN200 calims 40 hours!
At first I wash shocked at the Idea that Sony would cap their own product like that (only 62,5% of the previous model's capacity).
I personally do not care for the nocie cancelling feature that much and would rather have the extra battery life (especially if that feature reduces the capacity as much as it has done in this case).
Then I thought it made more sense when I read that the 25 hours is measured when noice cancellation is ON.
Though, I can not find any information on how long the battery lasts when the nocie cancellation is OFF.
Some of the questions that this raises:
- These models look quite similar and the older BTN200 seems to be going out of stock soon, but the names are not very similar at all. So is MDR-ZX550BN really a successor to BTN200?
- Are there any minor or major differences, other than the ones that I listed before?
Last and certainly my main question:
- How long is the expected (up to) battery life on the MDR-ZX500BN when the nocie cancellation is OFF?

Answer 1

Never mind.
I found it.
However, It says nothing about it on Sony's dedicated website for my country (Sweden).
I found it on the US website.
It can handle up to 29 hours of music playback with the noice cancellation OFF...
That is still less than 75% of the older and much cheaper BTN200.
Sony... this is not good.
While 29 hours is still quite good. The much higher price (effectively the double in stores, here in Sweden) and extra (even if it is minimal) weight, just won't cut it when your older version is way better.
I have not tried the noice cancelling feature on this particular model. But a lot of reviews says that is the weakest noice cancelling that they have experienced and that it is quite useless.
What the older BTN200 had going for it, was low weight, low price and the most astonishingly superior battery life. If something that makes a more universal impact on society, like an electric generator, was engineered to be as efficient as the BTN200 is among bluetooth headphones, I bet Sony would win the Nobel prize.
The successor MDR-ZX550BN has managed to be worse on all these points, is just generic and hardly worth the price it has.
I have decided that I will buy two (maybe more) BTN200 for the price of one MDR-ZX550BN. So that I may have a some spare ones,  just in case Sony does not improve on upcoming versions.
If someone who reads this has any power to influence Sony's decisions on future models. Please make them realize this!