Yeah, ok, that makes sense.
1) What's the biggest site the SiteMap Generator has crawled?
2) Are the sitemap files created along the way, or are they all created once all the crawling is done? For example, my 2.2M page site will need 45ish sitemaps. As it crawls 50k, then 100k, etc will I see the sitemaps created along the way, or will it wait until the very end before it creates those files?