I bought a Berkey Light with flouride filters (the flouride filters have to be purchased seperately) back in February and I'm very happy with it. The entire package (with flouride filters) cost me $292.00 over the counter at a dealer in Austin, Texas. I use it for drinking water, coffee, tea, ice cubes, etc.
I'm not really familiar with the Propur system price or performance. I can't imagine them being a great deal different from one another. The Propur filters are silver impregnated to kill bacteria, but I believe Berkey also developed silver impregnated core filters for their systems so they wouldn't be outdone by them.
I would suggest looking at their websites and compare information... Specifications, price, etc. Either one is leaps and bounds better than drinking straight from the tap. Even an inexpensive Britta filter pitcher is way better than nothing at all.