I'm now 2 rides deep on the DH34s.
Only one regret so far, not to have got them sooner.
Climbing
First, they suck in tarmac, for real. If your access climbs are paved I'd steer away from these.
Second, surprisingly, they don't suck everywhere else, at all. On anything that's not pavement such as dirt paths, cobblestone or gravel, they climb fine. A little slower to accelerate and marginally slower rolling than the WEs, but perfectly doable and the handicap can be met with a couple of weeks of training.
Third, they rock at technical climbs. This was the big surprise for me. A big percentage of my climbs are steep and technical and I was amazed how well the DH tyres performed there. They're way better here than the WE. In situations where I'd have to sprint to gain momentum or do lots of body English to keep traction with the DH34 I can just sit down and tractor through, saving energy. I know, it sounds weird to praise a DH tyre for climbing performance, but I invite you to try it.
Overall, this was so uneventful that kind of made me wish I had went all the way down the road for the DH22.
Downhill is obviously where they shine, but I guess everyone already knew this by now. One relevant detail is wet/mud performance. Michelin advertises these as an hardpack tyre, but they manage to do well in winter conditions. I'd say they're roughly on par with the WE on the mud/loose, the front maybe 5% worse at most. Makes me think how superlative the DH22 should be in the winter.
Anyway, really happy. Are these for everyone? I don't think so. If you have to climb a lot on pavement, value a very reactive and poppy bike, ride mostly flowy trails and never had issues with casing resistance, then I'd say to look somewhere else.