Roomba Battery Replacement

I’ve got an old Roomba that came with the 12x1.2v Sub-C NiCads.
I’ve rebuilt the battery twice when some of the cells reversed.
Both times it worked like a champ for a while.

It’s gone south again, let it run too long. Many of the cell are so poor that it’s not worth messing with.
I did cobble together a 4S 18650 pack and it did run – for testing purpose. But obviously I didn’t want to let it near the charging station.

iRobot wants a hefty price for a replacement. On Amazon, an OEM is $63.
There are plenty of cheap NiCad or NiMhs that claim all sorts of bogus mAhs that cant be had from a Sub-C sized battery. Way too many clearly fake 5 Star and lots of poor reviews too.

I have found a few replacements that seem to have 4S-2P 18650 packs with a BMS inside.
https://www.amazon.com/MELASTA-5200mAh-Lithium-Replacement-Certification/dp/B07V2FBFWR/ref=sr_1_30?dchild=1&keywords=melasta&qid=1593283530&sr=8-30

And
https://www.amazon.com/gp/product/B0749NJZ9X/ref=ask_ql_qh_dp_hza

And the brand Melasta has all sorts of batteries/accessories associated with the brand.
Other similar packs just seem to be re-branded stuff. Looking up a maker and seeing junk and kids toys is not confidence inspiring.

If it’s crap, at least I can add to my ever growing pile of pulls.
And perhaps a rebuild down the way if it works well.

Somebody with a 3D printer could make money selling kits to replace batteries in all sorts of stuff.

Anybody have any experience with the brand or one of the Roomba batteries?

Thanks,
All the Best,
Jeff