The Leather Rejuvenator can *really* work miracles on dried out leather. Worked for me when nothing else I tried would. Don't know how well it'll work for somebody else on different leather though...there are a lot of variables so YMMV truly applies.
I'd be a little careful with the Undercarriage Spray. It seems to be *extremely* silicone-rich, and while *I* am not overly concerned about that, it can make for issues in some situations.
It'll make your garage floor/driveway *VERY* slippery, especially when wet. As in, "be careful!" slippery.
It's a PIA to clean off of stuff too...from the medium you apply it with (I wouldn't just spray it) to your hands. It's simply very messy, slimy stuff. But no, that doesn't mean it'll attract dust/etc., at least not all that much.
BUT don't get it on surfaces where you don't want it. Don't let it get on your paint (e.g., mist from spraying it). No, it won't just wipe off cleanly with a little QD
But yeah..for what it is, and what it's made for, it's good stuff. Has what I consider a neat, if industrial, smell.
...be careful, it get's $$$$ fast !
) and there's less chance of wind/air-born stuff/etc. causing issues.