Congratulations on your new machine !
I have both a Steamer and a Mytee HP60 Spyder Extractor, and I use both on really bad dirty, greasy carpeting, because the steamer will pressurize up a lot of dirt from the very bottom of carpeting and the heat will help loosen up the really dirty places so the Extractor can come along behind and rinse and remove all the gunk.
Now, this doesnt mean that you cant get by with just one of these tools or even use them at all, but in my humble opinion, to really get carpets clean short of pressure washing (which of course, you cant do inside, this is just the removable floor mats), this is the way to really get all the dirt out of carpeting.
All you have to do is empty the recovery tank after extracting carpets and see all the dark brown water come out to know you really cleaned them well.
Now, some carpets may not need all this work, but here in the Northwest, the land of Composting material EVERYWHERE, I need to do it this way to give my Clients the best possible results.
A Steamer, if its a more expensive one, will also be able to clean the Dashboard, vents, blow out all the gunk in the door pockets, clean all the spilled latte's from the console, etc., and clean leather and other things as well.
An Extractor that is just an extractor, will only be able to clean and extract carpeting, cloth seats, etc., rinse and REMOVE the gunk from the surfaces..
So, hope this helps you out with your project !
Dan F