My pillow helps me somewhat. It doesn't help my back though, for that I need a decent chair or lots of normal pillows. What it does do is lift baby for me slightly so we feed more comfy. I find it hard to support baby's body whilst getting her latched, all with two hands so the pillow helps.
FYI this is what I have (I actually have two, one downstairs and one upstairs)
https://www.mothercare.com/Widgey®-...- Feeding-_-&gclid=COCdycOPz8ECFUT4wgode4UAVQ