Water Filter systems for mission use in Africa

I came across your website online and am very impressed with your water purification products. I am a registered nurse working for a non-profit missions agency in West Africa and have been doing a lot of research on water filters for our members to use. The water here is not potable and cholera is a constant problem in many parts of the country. People here are using the Katadyn "bucket" system, Pentapure systems, and trying out the Sawyer filters. We have found pro's and con's with each system and I am constantly on the lookout for a product that will provide better water quality and that is easy to use.  A couple questions I had for your company are as follows: 
1. Some people report "arthritis-type" of symptoms and pain after longer term use of the Katadyn (often ceradyn candle) system. Have you found complaints like this with your system. I realize that a company does not want to advertise any side-effects or adverse events of heir product, but the reality is that we have to drink filtered water here every day and this last many years for some people if they live here. I think it is important to be aware of some of the long-term effects of use.
2. Does your company offer a purchase price for non-profit organizations, especially if the systems and replacement candles are bought in bulk?
 Thank you for your time and many years of making a quality product.

Doulton has been a leader in Emergency filter systems since 1828 and there has never been side-effects associated with using these filters. It will efficiently filter out cholera and other pathogens to the highest degree and provide safe drinking water for your members in Africa. They are supplied to Relief Organizations across the globe, ie, the Red Cross and Unicef, as well as, militaries in operation.  We would be happy to provide a 30% discount off these systems if purchased in bulk quantities.  International shipping, if that's the initial shipping destination, can become quite expensive but we would be happy to provide a quotation or refer to you the appropriate department.
 Please let us know which filters you are interested in along with the quantities you see and we can provide a Quotation for you to consider. Please, also, inform us as to where they will be shipping to.

Thank you for your prompt reply! I appreciate your feedback and information. I am very interested in your system and I talked to our directors here and they would like to look at all the options before ordering.
 I am wondering if I could order one system for myself to try and use as a "test model" over here? Would the 30% discount still apply, or is that only for bulk orders? 
We do have a shipping and receiving center NC that we use and they ship things over here in a container. That way the shipping costs are much more affordable. :)

 What gravity filter would you like to test-pilot. The beauty of the Doulton system is that is has been produced for over 180 years and is quite established as far as its' performance is concerned, in Europe more so than U.S. That being said, I understand your need for testing before purchasing in a bulk quantity. We would be happy to provide a 15% discount off a single unit for you to try in your application. Please let us know which filter you are most interested in GSS2 or LP5
and we would be happy to send you a formal quotation.