If you want to get a Rode VideoMic ($170 w/boom & cable) paired with the PalmTrack or something similar (under $100) go right ahead. Better sound is better sound, so it's a starting point. Just keep in mind that you will not be able to upgrade, although they can be somewhat useful later on.
At the prosumer level the DR-100 and H4n both have their own problems, as do the AT897 and the NTG-2, which I have detailed in numerous posts.
You finally hit semi-pro with the PMD-661 or the FR2-LE recorders and the NTG-3 shotgun.
I'm not an equipment snob; if $300 is your budget you get what you can afford and save up for the next step up. Just be aware of the limitations.