Disc brakes vs rim brakes on front tandem wheel

[thing1]

Remember the tungsten carbide is only a coating (blasted into the rim at super-sonic speeds). It's not the core material the rim is made of. The total mass of the tungsten carbide will be relatively low, and hence make a very small dent in the heat capacity.
The bulk of the material is still Aluminium.

I've also noticed that CSS rims don't seem to get more than "a bit warm".

[321up]

We are trying a front disc brake on our Landescape to avoid rim wear over the winter - works fine for normal braking but it does not seem to bite as much for very hard braking compared with the v-brake with swisstop pads we were using.  We are using Aztec Sintered metal disc brake pads (http://www.singletrackbikes.co.uk/products.php?show=11852) which I was pleased with when previously used on our rear disc brake and found they lasted significantly longer (and are probably more resistant to overheating) than the TRP disc pads.  However our 600km round trip to ride an Audax from Tewkesbury at the beginning of January wore all the pads to the extent we ran out of adjustment on the adjusters (needed to release and pull more cable through) and I think the pads will need replacing soon.  It was exceptionally wet, but I think the rim brake Swisstop pads would not have worn down so quickly.  I suspect that rim brakes have a lower running cost than disc's for the front brake.  Based on my experience thus far I think disc brakes are fine for the rear, but I prefer rim brakes on the front.  I’m planning refit our front v-brake at the end of the winter (before we do any very steep descents).

[The French Tandem]

Thanks for sharing your experience 321up! I have always been  skeptical about the use of disc brakes on a tandem, at least as the main brakes.  Your experience makes me think that we should keep on relying on the good old rim brakes.