Not buying it...yet!
I charged up my iPod Touch and my original iPad.
My iPod has been not charged for over a year.
I have been using it and it appears that it is working fine.
I just charged up and powered up my iPad after nearly three years and it charged up fully between 4-5 hours and I have got it active and, again, appears to be operating normally.
I will confirm any issues when I let the batteries discharge some to see if there are any charging issues or if the battery won't charge from a partial discharge.
Otherwise, currently, my old iDevices seem to work fine.
They connect to WiFi, the older Bluetooth spec protocols connects to some of my current Bluetooth accessories, but not all of them.
I can get the Bluetooth to work on one Bluetooth speaker system, but not the other.
My original iPad and iPod Touch Bluetooth connect to one of my Bluetooth speakers, but for some reason won't connect to other, but not too worried about this since both of these ARE over 6 year old iDevices.