Battery advice and will it fit and work?

Hello,

I have MBP 2015 Retina 15" dual GPU and I am looking to get a battery for it. I do have a dissent experience in fixing MacBooks 2011 to 2015 and the glued battery is not an issue, i have done those replacements.

Currently my battery holds about 4.5 hours of browser use and 2 hours of Adobe use.Really want longer battery life, as close as possible to OME 9 hours.

I have couple questions:

1- Is there a difference between 2013, 2014and 2015 batteries ? I have seen some places selling the mid 2015 bat saperatly from 2014/13 models and some places selling 2013-2015 bat as all the same.

2- What is the best place to get a good battery? Apple is charging $200 for the replacement, and they also replace the top case, which is a good deal, however my laptop is in mint shape, therefore i don't really want to do that and spent so much on bat.

Besides the Apple, I came across OWC and iFixit batteries which had better then average reviews but still we not even close to Apple. And then there is Amazon batteries, which is not great to say the least.

From everything i read, my understanding that non of the third part batteries getting even close to 9 hours... is that the case?

If anyone can recommend any other brand as a good alternative to apple i would really appreciate it.

Thanks you