I was on the fence like you. A neck problem with a recent thumb injury were 2 of the reasons for my curiosity, but also the efficiency and speed. I kept searching for a recumbent shop where I could test one out, but couldn't find one close enough. I have only seen less than 5 recumbent bikes on the road in my life, all going in the opposite direction, and have actually seen more hand bikes than actual recumbents since Para-Olympian hopefuls sometimes train on 1 of my routes. I started to give up hope of getting a recumbent, and I felt it would pretty much put an end to any endurance cycling I had hoped for.
Finally, a lightly used one became available online (here) and the owner shipped it to me pending payment after giving it a whirl. The wife wasn't completely on board, claiming the lack of them here is a good clue they aren't good. In short, I am happy to say that I am glad I went ahead and bit the bullet because I absolutely hate regret and would have been feeling it for years.
In simple terms, the more upright the seat angle means the more stable and easier to learn on. The more laid back = higher speed. I didn't fart around and go the safe or simple route. That is not my style. I went straight for the V20 because I am interested in speed first and foremost. I could always stick a foam pad under the seat to make it upright if I really needed more time to get accustomed to the balancing act. It turns out that doing what Pollock wrote is exactly what the doctor ordered.
After a few days of wobbling around on slight declines and a couple of weeks of occasionally screaming like a little girl when I weaved too much, now I keep it pretty straight and my recumbent legs are probably about 95% as good as my DF legs were when I made the switch. Basically, I went from doing about 10,000km a year on my 2 DF bikes straight to the V20 with only a short breaking in period.
I don't know if a recumbent will help your numb foot issue, but I can confirm that the reduced weight on my hands allowed my thumb to recover, I don't have neck issues anywhere near like I did on the DF bike, and the large contact area on the seat is simply a no-brainer. I really wish I would have bought a recumbent 5 years ago when I first really started thinking about it.
