How many sessions for filtering water? I'm sure it depends on the amount of silt. The wet filters are a little fragile too. I have used a #2 cone and filter and they do a good job of cleaning up the water, but the cone takes up nearly as much room as a cook pot and it does add a couple ounces.
I thought this was a clever design and I couldn't resist making a Seal-A-Meal copy. I have tried to work compact water carrying methods into my survival kit and this little zip-top bag and pre-filter system is the best I have seen so far. A one liter Platypus works great but for the neck and cap making it less compact.
I don't do a lot of multi-day trips, so the holder and a few filters are more than enough for weekenders. Most of the water I encounter is clear, but you do need to have some methods for pre-filtering; of course, a bandana or micro towel will do the job too. This is so light and compact it can just be part of my regular cook kit. I use instant coffee most of the time, as the wet grounds are a pain, but it is nice to have real coffee. When we car camp, a Melita cone and a thermos are our primary coffee making kit.