We've got our first 'open' TT next week on the tandem. Wondering which front wheel to use, want to go fast, but don't want to break anything. Race is 10 miles on smooth roads. Tandem is a fairly solid lump, team weight about 130kg. Choices are:
40spoke, suzue hub wheel with 25mm gartorskin tyre, box rim.
specialized tri spoke, 19mm tub off my solo tt bike, apparently they are bullit proof but really don't want to break!
36 hole rsx hub mavic sup4 box rim, with michelin pro race 2 23mm.
32 hole dura ace hub on mavic open pro with vittoria corsa 23mm.
Kysrium elite with michelin pro race2 23mm.

The trispoke is going to be by far the fastest. And I'd bet it's as strong or stronger than all but the 40 spoke tandem wheel.

I've ridden a trispoke on single bike at close to 100kg myself. I would think you'd be fine at your team weight.

We saw one Tri-spoke front wheel at the Berkeley TTT today in the tandem division.

From another POV, the wheel significance depends more on your likely average and
sustainable speeds. Aero wheels such as the trispoke are not going to offer much
if your average is down around 20-22mph, but will contribute significantly (10-30sec)
if you are 26-28mph or above. FWIW, we have found that aero bars for the captain
make about a two mph difference in bike speed between 26 and 30mph. IE that is the
drop in speed at the same cadence on the level when the pilot changes his position
from aero bars to hands on the brifters with bent elbows. If you are accustomed to
such, try mounting them on the tandem, you will find it MUCH more noticeable than
trispoke versus 40spoke wheels. If you aren't give it a try.

likely average speed is 26-30mph. We did 25mph on a slightly hilly course at the end of last year without tribars. I have found some clip ons to fit, I use tri bars on my solo tt bike. I've thought of another option, that my commuting wheels have a semi deep section (30mm including breaking surface), 105 hubs, 36 spokes. They might make another compromise between strength and aero and cost if it breaks.

Tribars on a tandem are a pretty impressive aero upgrade but
do require a bit of practice in changeover from brifter to tribar
and back again as shifting can be problematic on up and down
courses. On long fairly level stretches they can can make a
real difference in speed and on a downhill can give you 3-4mph
bump to above 40 on a hill where a singlet would coast at 32-34.

should be only 5-10 shifts required all being well. still hoping it isn't too windy though.

I find ridding with aero bars on the tandem (Santana) to be more stable than on my single. If shifting is needed then I take my right hand off the aero bars, shift, and move it back to the aero bars (in 1 or 2 seconds). If the climb is >2% and longer than a few hundred feet then I ride on the drops. We use the sweet 16's front and back. Wer use to average close to 25 MPH on a flat 10 miles course.