Daryl, good to hear, my last 5 day trip I used most of that, except for the prefilter part, and had no issues, but the prefilter is something I think should extend the cleanout time, coffee filters like that are a few microns, no idea how many for that one. That was clean pacific northwest columbia gorge water, though some was from very small streams, like the one in the video, which I think you have to consider reasonably dirty in terms of suspended dirt particles in the water that are small.
My small syringe however I'm not certain about in terms of being a good idea, I have to check that, in the other sawyer thread going on someone posted an email from Sawyer noting that the first plunge should be strong to avoid forming channels in the mass of tubes, ie, clean in center, dirty on outside, not sure if the small syringe I found would create that much pressure, I'll take another look at it and see.
The large syringe with the tip that goes into the tube however would certainly improve the backflushing if you use a syringe. You might try that before backflushing with the sink, you get a lot more first oomph pressure on the first squeeze or two I think than a sink will provide. But maybe not, I don't know.