I was looking into XML sitemap generators and one that seems to be recommended quite a bit on the forums is the xml-sitemaps.com They have a few versions though. I'll need more than 500 pages indexed, so it is just a case of whether I go for their paid for version and install on our server or go for their pro-sitemaps.com offering. For the pro-sitemaps.com they say: "We host your sitemap files on our server and ping search engines automatically" My question is will this be less effective than my installing it on our server from an SEO perspective because it is no longer on our root domain?