I refrain from making a recommendation, but here are a couple places to checkout:
<A HREF="http://www.arstechnica.com/reviews/cases.html" target="_new">ARS Technica</A> (has some of the latest reviews)
<A HREF="http://www.upgradesource.com/advice/advice011002.html" target="_new">Upgrade Source</A> (provides some comparisons & advice)
<A HREF="http://www.mikhailtech.com/articles/cases/chieftecmatrix/" target="_new">Chieftec Matrix</A> (I know you said Mid Tower, but I really like this case)
<font color=purple><b>Listen twice as much as you Speak, better yet Think twice.
</font color=purple></b>