The MacBook Pro 2015 (13 and 15) are amazing, but they have glued-in batteries. iFixIt says it would take 45min to 2h to replace, and it is rated "Difficult". It's the only reason why I won't buy them on eBay.
https://www.ifixit.com/Guide/MacBook+Pro+15-Inch+Retina+Disp...
https://www.ifixit.com/Guide/MacBook+Pro+13-Inch+Retina+Disp...