There is an interesting article that I recently came back across (it was written over 5 years ago) about sensible recording levels and the use of VU style metering when recording here:
http://www.massivemastering.com/blog/index_files/Proper_Audio_Recording_Levels.php
The crux of it is that it is much more important to your sounds to work with your analogue gear (preamps mostly) to their intended spec with regards to levels, than to attempt to use all of your bits in digital recording. That may or may not make sense to people, but if in doubt, check out the article yourself, and try the experiment it spells out.