We've tried several in the past decade or so. We had a Sleep Number which was straight up horrible. I tried every number on the thing and couldn't get comfortable. We then tried a "Puffy" mattress which is an internet mattress that comes to you in a small box and expands when you take it out of the vacuum bag. It was a little too soft for my back after I herniated a disc, so we swapped it to our guest room and then we bought a "Layla" internet mattress. It has two sides to it, a firm and a medium. We both love it.
The internet deals have really caught on lately. They come in a small box so you don't have to take a truck and pick them up, or carry a big mattress up the stairs. You literally just unbox it, cut the bag that it's in, and it swells up to size.
In addition, most of the internet mattress firms say that you can try it out for 30-60-90 days and if you don't like it, they will refund your money and donate the mattress. Hard to beat that.