A few questions before I saw what I 'recommend'.
1) If you're into landscape, especially in dim lighting conditions now due to the ongoing winter in the northern hemisphere.. bring a tripod. Its invaluable especially when you want to shoot yourself in the scene. Or, if you think you can live with it, get a GorillaPod (believe you have access to the OEM copies at much less). A 3kg rated one can be had for as little as SG$22/- in some places online. Or you can look for one of the superlight Benro TravelAngel series of tripods, about SG$350/-. (I actually own one and find it so easy to carry around, I use it a whole lot more often than my 1.7kg one... )
2) If there's plenty of walking, invest in 2 items,
i) A good pair of walking/hiking shoes. (THink you can get them pretty cheap in China)
ii) A good camera backpack- The Flipside ones are pretty well designed, but they
seriously are not designed for extended trooping use. They do not have a good/firm
waist/hip support strap. Carrying for long hours, with something like 4-7 kg on your
shoulders, you're gonna be aching in agony at the end of your first day out. The
LowePro Primus AW or any of the other brands of backs with an equivalent waist/hip
strap will be a much better option. They are bulky no doubt... but with good reason
(I'll get back to that shortly). Your computrekker seems bulky but its a close match
actually.
3) Security - Its often seen that walking with a backpack in areas with pickpockets might seem an issue, but quite to the contrary. Its really how you carry them. In fact, if you've walked down a crowded street such as Chinatown with the night bazaar now with a bulky backpack, you'll find that its actually easier if you carry it in front of you rather than on your back, and its safer too as its almost impossible to pickpocket !
4)Other items to carry, as mentioned, you need a backpack with spare capacity to carry other stuff besides you camera gear. (this was discussed in a thread not that long ago actually). Typically, besides your camera and lenses, you also need space for spare batteries, filters, cleaner, and things of the sort. Possibly a tripod too. If you're doing a lot of walking, you should have some water with you too. Not to mention some simple finger food or a chocolate bar especially in cold climates. TO mention of which, you need extra warm clothing. Unlike the tropics, the transition from day to night in those places mean a very drastic drop in temperatures, easily 10 degree C within 1-2 hours. So, you'll need clothing with you to tide through the whole day. Wear everything and it'll be too warm, but you still need that extra top when the temperature drops as night falls, so.. yah, where are you gonna put it ? The weather can be no joke in those areas. My first time in British Columbia mountains in Canada in 2000 gave me a real shock literally. Daytime was a really nice 23-27 degrees. But once the sun set (5.45pm), within an hour it was below 20 degrees C, within 2hr it was 15 Degrees C, and it went to about 11~12 degrees C by about 11pm! And it wasn't even autumn yet!
Besides these, you still need to carry other stuff such as your wallet, passport? If its wet weather, maybe a cheapo plastic raincoat for that matter?
All these add up in the space required, so... yah, ideally I would like to carry a small 20 litre backpack like I can in Singapore, but practically, you need something around the range of 30-35litres when you go travelling due to the extra little things that you need to cater for.
Not to forget, what if you bought souvenirs that day ??
Hope this has been of help for your planning...
