My wife and I are traveling to China (PEK, to PVG, 4 cities en route) including a side trip to TIbet. Trip is in May, via Discovery Adventures (thus a guided trip). We always seem to pack too much and wind up with a large duffel-bag suitcase each. We see others on our tours that can do 10 days out of a carry-on. Your advice is solicited for packing much lighter. We have to deal with temps from near freezing to room temperature. We probably won't have washing facilities (hotel or even a laundromat). We have no problem buying things now if highly recommended. We do have some fast-dry wicking tops, but that's all. Ideas, anyone?