I am familar with Coby. I would avoid it on the name alone.
Namely, I would worry about microphone quality number one, and number two.. I'd be willing to bet it locks up for no apparent reason.
I have an application on my HD2 I use for recording, even gets audio pretty well from inside a coat pocket.
At any rate, I would look at products that are at the very least $50 price range. Its hard to judge mic quality just by looking at specs on a box, but you should get something decent in the $50 to $100 segment.
I am sure guys around here that have stand alone recorders have suggestions beyond that.