They work for me. What doesn't work?
Maybe with some of the stranger characters the base feed could use some additional formatting, but the sitemap should work fine
ATM, when I try to set the url to something other than index.php?route=feed/google_sitemap and then visit that URL (for example, domain.com/googlesitemap.xml), I either get a 404 or it just redirects to my home page.
I tried being fancy about it and using a redirect within both .htaccess and through server-managed redirection (through cPanel), but since the ? is a trigger character for SEO URL rewriting it just redirects to my home page with a halfway rewritten URL. It might just be server settings, however, if it works properly for you.
I could also create a dynamic file that just rewrites the content from either feed/google_sitemap or feed/google_base as an .xml file, OR I could convince my boss to just let me buy your RSS feeds plugin (THIS).
My main beef is still the search algorithm. I'm going to install the AJAX search suggest and then use a sitemap as both my 404 and the "no products found" and see if that helps.