rdtompki

Dan,
First, congratulations!

I really like the Campy on our DaVinci. I do sometimes blow the 36 to 12 downshift up front, but I can flick my right thumb and upshift 3-4 cogs. I love the RD shifting. I don't know the chainring sizes on the Shimano setup, but I would think the decrease in range might be more significant than the fewer gears. That having been said I switch to the 12-27 just so I could have closer spacing. Wouldn't want to give this up on account of having a triple up front.

Regarding brakes: We're a relatively heavy (340 lbs?) team and the rear disc setup seems to work very well. I would have said I was a slow descender, but your perspective will change dramatically on a tandem (mine did). Darn things are so stable. Others wilth extensive experience will weigh in, but as long as you don't use the disc as a drag brake I would think you'd be fine with just a rear disc.
Wheels: I'm sure the Rolf's are stout. Just keep in mind that you can't (at least I can't) bunny-hop a tandem and they are not as last-second maneuverable. You will hit potholes. The DaVinci wheels have proven to be very stout. I believe they make these wheels in 36 spoke which you might consider if you're not doing loaded touring. I could see getting lighter/more aero wheels just for events so my team's carcasses can go .1 mph faster.

I sense a bit a geek in you Dan? We're running a Garmin 705/305 setup front/rear. Works very well and I can tell if my stoker stops pedaling. Now if I could only read her heartrate.

We've also adapted the Interphone wireless intercom per Tandemgeek's instructions (I think). My high frequency hearing stinks and with this setup we barely have to whisper to communicate. Batteries are internal, but last about 5 hours and work on singles (450 ft. range). Also, I can hear my stoker breathing - keeping her honest as it were.

There can't be too many DaVincis on the road!