urbansurvivalist,

Those cautions about a contaminated container applies to all purification systems. Even chemically treated water purification systems have this problem. Some of those systems suggest swirling the treated water on to the surface where you are to place your mouth to disinfect the surface. But that is not an effective technique. Chemical treatments require that the chemicals be in contact with the contaminated water for a period of time, up to 4 hours for some pathogens. Even boiling water purifying does not decontaminate a dirty drinking vessel unless it is properly cleaned..

If you go to the hydro-photon.com site and open the Users Guide, note on page 3 and again on page 4 step 4 of the Operating Procedures, sealing the mouth container with the SteriPEN, inverting, and agitating will purify the contents. Pay particular attention to the agitation process described on page 5. Page 9 has the warnings you referred to. I use the prefilter they provide as detailed on page 17 but only to keep clean the portion of the mouth of the nalgene bottles I use. I don’t use it as a filter. That is what I use the Mil Bank Bag Filters for. See the note on page 18 on Immersion.

Immersion:
Note: The “O” ring on the rim of the filter base seals against the flange of the water bottle neck to prevent untreated water from contaminating the threads and outer rim of the bottle.

Once you get familiar with the process and use common sense it is faster to do than described.

If you are in a restaurant or other public place in a foreign country or in some locations in our own country, it is easy to disinfect served water without causing a public stir or insult