The bast RSS reader I've found for my Mini, which doesn't seem to run any OS beyond 10.4.
RSSOwl imported all of my feeds from Google without a hitch, and has ample viewing/organization options.
Give the choice between native and Java, I would certauinly choose native. But in this instance, I didn't seem to have a choice. Which is fine, as RSSOwl works wonderfully. Java or otherwise.