Here are the pictures that I took during installation.
Warning... There are several.
'09 Fit - Cargo Mat Installation - a set on Flickr
I agree that it might be beneficial to add some more velcro, but the mat seems to be fairly well fastened down.
As you can see from one of the images, the mat is rather thin, but very sturdy. Now, I didn't got after it with some nails or anything to test this, but it feels like thin tires... It's rubber.
I'm still using the regular cargo mat, but only because I paid for it, so I might as well. I keep extra washer fluid with me at all times - wouldn't want to get caught in a snow storm (which means dirt and salt will end up on your windshield when you're driving) without having washer fluid, so having that lipped cargo cover may be handy. =/
As for the all-over cargo mat. I have no intentions of trying to permanently affix it to my seats/cargo area. I like that it's rather easy to remove, for cleaning purposes. The likelihood of water & mud getting in my car at somepoint is... well... not unlikely.
I couldn't get a picture of it with the regular cargo mat in there as well, because my camera had died right at the end of the installation.
If anyone's truly interested in seeing what it looks like, let me know, and I'll snap a picture.
I included pictures of the installation instructions, for your curiosity/satisfaction. If anyone wants a nice/pdf scan of this, I can take it to work and scan it for ya.
Well, I'm posting this on the run, so hopefully I didn't miss anything.
Let me know if you have any questions.