I bought this pump because my Seattle Sports Paddlers Bilge Pump is just a tad too long to fit transverse behind the seat of my kayak and wanted to make my deck cleaner so I thought I'd try a smaller pump I can fit behind my seat so I do not have to bungie a pump to my deck.
The plus of this pump is it does fit nicely. It's also cheap; I got it on sale for <$14.
The minus is it doesn't work quite as well as the Seattle Sports pump. It seems to have more resistance on the up stroke, it doesn't project the water as well, and it doesn't pump as faster. But it's a smaller pump so some reduction in performance is expected. I figure I'll keep it behind my seat and the next time I have to pump out, decide it it's good enough to keep or not.
So bottom line, it is an adequate pump and it's small and cheap so it is one option that might be worth buying for some people. I suspect if you want a pump that size that works a bit better, you'll have to buy one of the models that's up around $30.