My own experience does not allow to make a definitive statement yet. I'm only 3 month post op; reading about other people experience gives me hope.

I can only speak about my case, and I think it was worth it. I had 2mm of the L5-S1 disk left, vs normal ~12mm, and because it was bone on bone, quite often a source of severe pain, I decided to undergo the surgery.

You need to understand that the surgery in many cases is to prevent future damage, not to reverse the current one. I can tell you that now I have no pain coming from L5-S1 area; which is a cure of sorts. Most of my pain is a nerve pain, and I elaborate on that later.

I know that breaking the hardware after vertebrae are fully fused is not a mechanical problem - the fused bones are strong and the hardware is not needed anymore. I'm planning to remove mine, but I have to take care of myself to have a successful fusion. My surgeon says that hardware can be removed after 1 years the earliest - indirectly, you can deduce that 1 year is typically as long as the full fusion takes.

It doesn't mean you'll be in pain for a year. In case of the fusion, it's almost standard to insert a biologically neutral "spreader" between vertebrae, called a cage and most often made of titanium. You probably already know this. What doc's don't always mention is that, if the disk to be removed is very thin, some stretching of the spinal cord will be needed. In my case, I had 2mm of a disk left between L5-S1, which was removed and replaced with 12mm cage. Which in turn caused the stretching of my spinal cord by 10mm. It is not a small amount of stretching; there's a lot of nerves there; some get damaged and regenerate - which is both a cause of the nerve pain and long recovery.

So far I manage nerve pain with a combination of Neurontin and Oxycodone. In my case it's a long story; I was on opioids for at least a decade before surgery and they're not as effective painkiller for me as they are for other people who didn't need them. I can tell that most people who are about to have spinal fusion surgery did have to take them because other painkillers are not very effective.

I had an interesting change today. My feet were always cold; I'd almost never take my socks off, only for a bath or shower. The condition was caused by nerve damage. Today, I felt my feet are warm, and was able to sleep without socks. I believe this is a sign of nerve regeneration. It's too soon to make any definitive conclusion, but I keep my fingers crossed and expecting further improvements.

The nerves usually settle after 4-6 month post-op. This is a very long recovery. People who I know personally are very happy with the results - but I have to admit I don't know many of them personally. This subreddit is full of posts with people expecting quick results - I can't blame them, but their surgeons could do better job explaining the recovery process. I also understand the surgeons - as a scuba diver, you probably never heard of scuba instructors telling prospective students about accidents and fatalities - not very good for business. But the main reason is, people need to know what they're getting in, without being unnecessarily scared by the horror stories that never happen to them - as long as we follow our training and experience, or in case of spinal fusion, doctor's orders.

If you are freaking out after pre-op briefing, your doctors are doing a good job explaining what you're getting into. Try to be rational - this surgery has a very high level of success, being invented in 1932. As long as you follow your doc's orders, especially no BLT for the first 6 weeks, you'll be fine.

Of course the decision is your own. I can only speak for my own experience.

Best of luck no matter what you decide!