@indigo I have a 2008 pre-Unibody 15-in MacBook Pro. That’s kept at my mother’s place. It needed a new battery so I got one for $44, this lasted four whole charge cycles before the system started insisting that I “service the battery.”
Which I did with a $75 battery from another supplier. That was much better, it behaves like a proper battery.
A decent new battery, installation of 6 GB of RAM and a 240 GB SSD make that machine quite effective.
Batteries don’t have to cost the earth to work.
/@streakmachine @kdfrawg