[LAU] Mic for accoustic (bass) guitar

Hi all, What would be a good microphone for recording both acoustic steel string guitar and acoustic bass guitar ? In the $200-250 range. I currently have a M-Audio Pulsar and am looking for a recording that has more of everything I hear from the instruments which does not currently gets in the recording. The recording sounds like a digital compressed version that doe snot have all the warmth and nuances heard in the room. Would upgrading to a $200-250 microphone help ? Or would any difference be made only with much more expensive microphones ? I basically would like to record as much what my ears are getting when playing. The recording tool is Ardour, with all plug-ins found in a Fedora 15/CCRMA install. Thanks for any suggestions/comments!