I've heard very good things about Dr. Regan.
Personally, I've recently had two level fusion at L4/5 and L5/S1. Both were done using the Nuvasive PEEK cage, and the L4/5 was done via XLIF, a minimally invasive method that went in through my side. It is a very small incision and barely hurts at all. The L5/S1 had to go in through the right front/side of my abdomen, because he had to go up over my hip bone. Even that was not majorly painful. I am three weeks out from this surgery (including a disc replacement at C5/6) and am almost completely pain free. (There were three separate incisions and an eight hour surgery because of 'surprises' part way through.)
I am only continuing on with my pre-op pain medications to avoid withdrawal right now while healing, plus a small amount of back pain from normal healing.
I had to travel out of country to get this surgery as I needed non-metal devices, having discovered that I am severely allergic to all of the metals used in spine surgery. I was able to find Dr. Luiz Pimenta in Sao Paulo, Brazil and traveled there for my procedure. He does, however, travel to the US regularly.
After reading the reports from some others who have had regular fusions, I am so relieved to have gone this route. My S1 had slipped forward ahead of my L5 vertebrae, causing a great deal of pain and putting my spinal cord out of alignment. It was not that obvious from my several MRIs or x-rays and he had to change his plans after starting surgery. If I hadn't had to do the L5/S1, the surgery would have been a breeze...no exaggeration.
My recovery now is mainly through sleep...my body is insisting on about 15-18 hrs of sleep a day, and I am listening to it
This is just to say that there are good surgeons out there and to keep the faith. Dr. Regan has a great reputation as I said above. I had to go through about eight different consults to find someone who felt right and I had confidence in.
Good luck with everything. You certainly deserve it.