Good morning - I like the idea behind the Raritan KO2 kit: with every flush a little bit of C.P. is pushed through the pump (I've a SuperFlush) and through the bowl to prohibit low tide-like odors. It's on the pricey side, but includes a metering valve that appears to be expensive to buy on its own so is probably not a horrible deal. Oddly, while lots of stores stock the product I can find few comments about the product in the forums. Does anyone here have good or bad things to say about it? Thanks!