Pure water and "Pureit"

I am talking about the popular brand of water filter (purifier) from Hindustan Lever, "Pureit".
I am a Pureit customer, since the last two years. I have been keenly watching the "Pureit" publicity, over the TV and newspapers. Last day, I happened to see a colourful brochure on this item. The data given there in made me reassess my earlier decisin to buy the product. But, I had already implemented by decision, and so a reassessment on the decision, however, is irrelevant.
But still, I just had a thought on the product, based on what they says.
Pureit has been compared with other conventional filtering (purifying) methods. OK..Ok..Pureit certainly wins. But a comparison with a UV-inline filter also has been projected. The tabulation of comparison clearly says that :
Pureit has low initial expenditure, and low recurring expenditure. For the UV filter, these expenditures are high.
Now, I have a disagreement on this claim, based on my experience with the product.
Initial expenses are certainly low. Thank God.
Recurring expenses are NOT low. Infact, it's very high; that's what I know. And remember, the UV filter has no recurring expenditure, but for the low power consumption.
Thye expenditure of Rs.1/- per 5 litres of purified water, is not true. It works out to almost Rs.1/- for every 3 litres. ie. Every litre costs you about 35 paisa. For the UV filter, I don't have the exact figures. However, I feel it should be much lower.

Pureit always talks about a 'battery'. Though initially I had a confusion over this term, I am clear about what it means. But, I know some people believe that Pureit works on 'batteris' !
{For the common man, batteries refer to a set of cells (dry cell or NiCd or, something like that ) for powering the device }. Pureit battery is just the 'chlorinating module' in the purifier. It has nothing to do with powering the same. This 'battery' needs replacement quite often; and costs you heavily.

I hope, HUL understands the common man's vocabulary, and use the right words. I know, a person deferred his purchase decision , just for believing that this fellow works on batteries (and it would cost him high and recurring).