Probably just me, but I found the other big name SEO plugin to be confusing. All-in-One walks the user through the set-up process in a way that made more sense to this SEO newbie. As for effectiveness, that’s a very subjective impression because we didn’t do a controlled trial and we changed several factors at more or less the same time, however our search engine rankings are looking much better. Now that the low hanging fruit has been plucked, we (I) have to buckle down and add more information page by page but that seems pretty straightforward.