All great points and exactly the kinds of criticisms I was looking for!

I am not all corned about carrying capacity. When I crossed the US my biggest problem was weight and not capacity. I had more than enough room to carry all of my gear and then sum and thats with all of the cheap bulky gear that has since been upgraded for this trip. The Lone Peaks will have a few liters less space than the Transit Epics I used on that trip but overall not a big difference I feel. With that in mind I am not too afraid of covering the important stuff with plastic bags. Trash compactor bags take up virtually no space and are big enough to cover the entire main compartment using only one if I felt like it. The Lone Peak Panniers also weigh significantly less than Ortlieb's so thats another plus.

You seem to be a lot more concerned about waterproofing than me which is another valuable criticism. However, if I may add another point against the Ortliebs, their method of waterproofing can be spoiled rather easily as I saw happen to two of by riding partners. One of them took a small spill on his bike which, while he was just fine afterwards, eat a decent size whole in his expensive Ortliebs and completely ruining their waterproof advantage. My other friend stupidly left some small food items at the bottom of of of his bags in which a raccoon quickly ate through to get at. Now I know Ortliebs have a great rep for being tough, as do many panniers I might add, small holes and punctures virtually eliminate their most attractive feature. If a pair of Lone Peak or similiar cordura panniers receive a hole or puncture they can be stitched up with just about any fabric laying around and the plastic lining on the inside can be cheaply replaced. Ditto by the way for bunggi cord attachment systems but thats another argument. If you were really concerned about waterproofing and just didnt trust trash bags for whatever reason you could buy Ortlieb dry bags that fit into a standard pannier for a fraction of the price of a whole Ortlieb pannier!

Another problem I have with Ortlieb is their attachment system, though apparently very strong and such, is highly specialized and I am unlikely to find replacement parts in the third world if something were to go wrong. Several other brands like Lone Peak and Axiom use simpler systems that work well enough but are more easily field repaired.

I never use my panniers off of the bike for sight seeing. I have what is essentially a dry bag with shoulder straps that I carry with me. It looks a just like a normal backpack but it packs down small and I use it to keep my cloths dry in my panniers as an added bonus. I find it is much more comfortable than wearing a pannier slung over a shoulder all day. To each their own though. I'll try and find a link for the product but I bought it here in Korea so no promises.

I am not entirely sure I understand your argument about something getting squished at the bottom of the pack. Would it get stuck in the zipper? If anything the zippers would help because the whole pack could be opened up at once without unloading everything.

Good points were made earlier about the reliability of zippers vs. Top loading panniers. Very worthy of consideration I think. However, zippers are simple machines, I believe anyways, and the advantage of not having to unload everything and have lots of organization pockets with no real weight penalty seems a good trade off to me.

Being able to clean off the Ortliebs is also another advantage to PVC bags vs other fabrics. However, I kinda like the looks of a dirty bag so its, forgive the pun, a wash for me.

How much stuff do you guys in the Ortlieb camp carry that needs to be waterproofed? In general, the things I need to be dry at the end of the day are:
1: sleeping pad
2: sleeping bag
3: clothes
4: a few small electronics (Camera,ipod,ect.)

What else is there? My tent usually goes on the back rack in its own dry bag that I bought to replace the normal bag it came with. Sometimes I put my sleeping bag or pad on the top rack as well, also in dry bags. Cloths go in my dry bag/back pack. All the rest of the stuff can get as wet as it wants too i.e. cooking stove and pans, bike tools, spare parts, ect. I am guessing the difference is that other people carry more expensive electronics than me like laptops, GPS, and SLRs. Expensive stuff like that I can certainly understand being paranoid about.

Maybe I just dont ride in the rain as much as other? Most of my tours tend to be relatively open ended. Meaning, that if the weather is bad that day I just stay in the tent and read or otherwise take a rest day. In Asia where I will have access to cheap accommodations on a fairly regular basis I cant imagine riding all day in too terrible of weather for too many days in a row.

Let me know what you think about this line of reasoning, pretty different approaches to the same problems.