Jason,
That's terrible to have those kinds of problems at 29! I hope that we can be helpful here. You've already received some very good information. I want to ditto, double ditto and triple ditto everything that Joey Sue posted, and second Harrison's concerns about Stenum. But as Bob points out, there are many hundreds of successes from Stenum; I would dare assert the overwhelming majority are successes.
Having read dozens and maybe hundreds of fusion/ADR outcomes, and having spent dozens of hours researching scores of peer reviewed research papers (for an insurance appeal), there are three surgeons that for my tastes seem to stand out (in the international arena). They are the ones that Joey Sue mentioned; Clavel, Boeree and Pimenta. All three are very conservative (unlikely to risk your long term health by performing an operation that you want but they think is unwise), extensively published (especially Pimenta), have far more ADR experience than any US surgeon, and consistently have good patient outcomes published on every forum that I've ever seen.
Dr Clavel did my two level cervical M6 ADR and I've resumed running marathons. His patients post excellent outcome after excellent outcome on the forums. I would note that every outcome I've read about has been cervical, not lumbar. I know that he performs lumbar surgeries, but don't know why only his cervical patients post on forums. If you consider him I would encourage you to look for as many lumbar outcomes as you can find.
I know of two of Dr Pimenta's patients that have very complex lumbar cases that were up walking around the day after surgery, and out touring Brazil the following week. Dr Pimenta is, I found, a highly published researcher that is profusely cited by his peers; at least as much as Dr Zigler.
Dr Boeree's patients have posted outstanding outcome after outstanding outcome on forums; cervical and lumbar. One thing that stands out about Dr Boeree is that Dr Zigler (possibly the most conservative ADR research surgeon in the world) referred a patient to him! This particular patient was very physically active until his lumbar problem. Dr Zigler told him that the ProDisc-L would not allow him to return to his active lifestyle, but that Dr Boeree and the implant that he used would.
Here is a link to a blog entry from this patient about that meeting in which Dr Zigler referred him to Dr Boeree and the M6-L prosthesis.
There are a lot of outstanding ADR surgeons out there, many of which are in the US. Are you physically active? Do you have any of the contraindications to ADR? Where are you located? Someone may have experience with an ADR surgeon that is near you.
Good luck, Jeff