I'm tempting fate really by starting this section when we're only halfway through the trip. So far we've been impressed by:
Our tent is no longer produced but I think the build quality is typical of North Face. After 330 nights use, we've had no broken poles. I think the flysheet will eventually sucumb, gradually weakened by mold growth despite our attempts to dry it every morning.
The bikes are great, we have had one rack breakage but they are jolly strong.
We tried Panaracer Hi-Roads which last ages but being slick are useless off road or if it snows. Also Panaracer Pasela Tourguards which are nice but not chunky enough for tracks. Then we discovered Schwalbe Marathons, they seem perfect for our style of mostly on-road but some off-road touring, and last a very long time.
In fact we fitted the tyres in Novosibersk, Siberia (we didn't buy them there, they were shipped to us by St Johns) and they went all the way to Australia, a distance of 14,000km, without a single puncture! Friends with a tandem used and destroyed a couple of sets of 26 x 1.9", but may not have been inflating them hard enough. I usually rode mine at 55-65psi, Ju's at 50-60psi.
These were fully waterproof for at least the first year of the trip, excluding a couple of holes in my front ones caused by clipping curbs. By the end of the second year they leaked a little, just as we entered S.E. Asia and monsoon rains! But basically they are very strong and work wonderfully when new. I did break a couple of the clips that the panniers hang from while we were crossing the Gobi, I'd recommend carrying a spare or two.
Sadly no longer made, but my Casio Fiva 101 went all the way with only a hard disk failure (IBM hard drive).
Likewise this took all the vibration, some dampness and constant use (10,000 photos!).