Responses to all the statements/questions above:
I don't need a garage or gas station pump. I know they work. I have an electric pump that also works but it's for the car and is a pain to take out for every ride (i.e., it would prevent me from riding if I had to deal with that every time).
I have a guage, it's just not built into the pump. It is mildly more convenient to have a built-in guage, however in my experience they are fairly inaccurate unless you spend a fortune on a pump.
The pin doesn't flip. According to the instructions, there is a little insert that screws into the pump hose head for filling presta tires.
Supposedly the pump works for both presta and schraeder valves, however I am under the impression due to the depth of the pin inside the pump hose head that this pump might be better suited for presta tubes.
The smart thing would have been to test this on a bike in the store...
sigh. Tomorrow, tomorrow...
It's funny because I can't find this pump online, and considering it's an $8 pump at Wal*Mart, I would have figured all kinds of people would have tried and rated it. Ah well.