To any forumites who may be interested, I'm using McGraw Hill Connect/LearnSmart in one course this semester and Macmillan Launchpad in another. It's been a mixed bag in terms of results. I'm not planning to use either system next semester, but I will use LearnSmart if I ever find myself teaching a high enrollment survey-type class in the future without institutional support for TAs or reader-graders. (I will *never* use Launchpad again. Long story).
I'm glad to elaborate on the above if any forumites are thinking about using these tools in their own classes.