This is as personal a decision as what kind of mattress to use at home.

Cheapo store model works just fine for some. Other people pay $3K for a Tempurpedic. We tried one and I couldn't stand it; I was up all night tossing and turning. It was returned a week later. Now, we have a super firm something or other brand. I remember the salesman trying to talk us out of it. "You'll hate it! You'll be back!" We love it. There's no accounting for tastes.

I have friends who swear by the Sleep Number bed. Others want pillowtops, foam mattresses, very specific firmness, etc.

You can't know without trying a bunch of variants, and it's best to do so on very short trips. Nothing like carrying gear when you were up all night cause you couldn't sleep.

Also, hammocks deteriorate over time, just like anything else. I still remember the "below the waste" section falling apart on a hammock I was sleeping on that had been a bit abused. That was quite the shock and felt like an earthquake...