i don't know from long term, my Mom was terminal and didn't last three months and the one we had was much better than not having one... but this was 25 years ago so i hope things have improved since then i hope the best for you and your wife, prayers up
Yea the big improvement is the low air loss mattress. It stems from a technology they developed about 25 years ago from what was called a Kinetic Mattress which in about 1988 cost tens of thousands of dollars. It's as thick as a hospital bed mattress {replaces it actually} and has huge chambers the air circulates through. Plus it is fully adjustable. Most Alternating Pressure Pads are pre set to hard as river rocks. The Low Air Loss matrass can also handle a lot more abuse. My wife sleeps with our Toy Ratty. On the Alternating Pressure Pad the dog would have busted it.
Really my wife's sore wasn't that bad till I put her on an alternating pressure pad. The vinyl holds in heat and breaks down the skin plus can incubate undesirable bacteria.