Suggestions for a backpack for Pentax 67 II Kit

Hi again,
Now that I have the start of a Pentax 67 II kit I'm now realising that my old Lowepro backpack just won't be able to accommodate this equipment. The kit I currently have is:

* P67II Body + AE Prism
* Lenses: 45mm, 55mm, 75mm, 105mm, 165mm and 200mm
* Filters (Lee ND Grads, Warming and Polariser)
* Pentax Digital Spotmeter
* Cable Release, batteries, cleaning accessories
* Tripod + Ballhead

Now I probably will settle on 3 lenses to take out on any one trip due to weight restrictions. I'm thinking 45mm, 105mm and 200mm for most of my landscape/nature photography. If I manage to get hold of a 100mm Macro lens I'll probably subsitute that for the 105mm.
I know there are a million choices are out there but does anyone have any Strong recommendations for a backpack which can accommodate this sort of equipment? Preferably I'm looking for someone who has used a backpack themselves for a reasonable period of time with exactly the type of kit above...
I think my main requirements are:

1. Comfortable on the shoulders/back for long periods of hiking/walking on all types of terrain
2. Able to attach the tripod
3. Possibly attachments for water bottles, etc
4. Lightweight
5. Waterproof
6. Configurable compartments
7. Ease of access to equipment

Any help would be appreciated !
Rgds
Rick

I find the Lowepro Vertex 300 pretty good for my bulky SLR. link. I've never had a problem with water, but if you're going on a long trek I don't know how good it would be.

Thanks for the replies.

From the suggestions so far (on this and other forums I posted the question to) the main choices are:

1. Lowepro (Photo Trekker/Vertex/Computrekker Plus/Pro Trekker)
2. Tenba (Shootout/Rolling)
3. Tamrac (777)
4. Osprey (hiking backpack)

I am expecting to hike on occasions for potentially a few hours/half a day to get to locations, etc before shooting so comfort is probably one of the biggest factors. I'll take a look at the Manufacturers website on each of the above and then see if I can try a few in one of the shops here.

Rgds
Rick

I have a Lowepro flipside 400 and Lowpro AW Trackker, the flipside takes two camera bodies, six lenses and bits easily. My only complaint is the lack of non camera storage, I can get a light weight raincoat and a lunch box in and that's it. The tracker has bags of room is comfortable but has almost nil external storage for non camera gear.

Just a quick update... I was down at the camera store today looking at a few of the bags mentioned. Here's my initial thoughts:

Kata Bumblebee PL220 - Was told this was the new update to the HB207 recommended. Nice bag which seems very light. Nice and bright yellow inside making things easy to find. Rubberized straps for shoulders but not too much in the way of extra external storage

Lowepro Vertex 300 - Nicely constructed and design, looks robust but not really too much in the way of carrying anything aside from your camera gear/laptop (ie would be hard pushed to put any clothing/food/water, etc)

Lowepro Protrekker 300 - Probably the most suitable for what I am planning in that it seems more geared for hiking as pointed out by tuco above. Nice external storage options which all seem removable if you don't need them or want to cut down on weight. Also a side pouch for a water hydration system so you can have a tube coming straight out of that.

I think I'm sold on the Protrekker 300. It's probably big enough for what I want to put into it. Any bigger and I think it would be too heavy...

Rgds
Rick