Do they really do a device swap?Bear in mind that Apple doesn't replace the battery when you service your iPad, they swap the whole device with a refurbished unit. Battery service is around $120 (USD, more for iPad Pro) and you're receiving a new (to you) device with a new warranty for another year* (plus other consumer protection in your region). I think Apple is a better route with the price being similar to your experience, but it depends on availability of course.
Edit: *As pointed out by Digitalguy, I may be wrong here.
Because that would be an incredible deal for the customer to do the battery repair say 8 years later and actually get a brand new non-yellowing LCD display.
Would be incredible if true.
If true, I may keep my tablets even longer just for the swap.