HI,
Wanted to present this as it was a surprise to me and it might be of interest to others.
My hiking partner and I just covered 400+ miles of the AZT here in Arizona. During parts of this hike one has no choice but to filter water from heavily used stock tanks (these are dirt dams in gullys which catch water and are used by the cows, elk, etc for water). Some of these tanks are VERY dirty with both the waste of the cows and the mud they churn up when walking and peeing/pooping in the water. Yikes! you say? Well... yes. But the interesting part is below.
I carried one of the standard MSR pump filters (about 13 ozs) as I figured that the extreme filtering pumping requirements of the stock tanks absolutely required one. My hiking partner carried the regular Sawyer filtering system (a few ozs).
In actual use sitting right next to each other it turns out that in our real world worst case conditions that the Sawyer would filter water about 50% FASTER than the MSR would. The basic reason for this is that the very fine particulates would pass right through the MSR and my bandana prefilters and hit the main filter. Thus I got 2 full pumps of water was all before the MRS relief port started ejecting water due to over pressure. I would have to take it apart and scrub, reassemble and repeat. It took me 90 mins once to filter 3 liters.
The Sawyer on the other hand filtered a lot more water before clogging and needed to be backflushed. Thus its better performance.
I acknowledge that in other circumstances the MSR will easily outperform the Sawyer but in really bad conditions it does not as found above. Given its weight advantage and its advantage in horrible conditions I would have to say that I now think the Sawyer best overall choice of the two for almost all long distance trips.
Wyo