I haven't bought rooting gel in years since finding out about this. I do this exact method with the aloe, but like to add a little liquid seaweed and Ful-Power. Not only does this work faster than any cloning gel I've used, but the roots I get are way more robust to boot. I believe I even read somewhere that cloning gels pretty much just extract aloe vera and most cloning gels are just synthesized aloe vera products.
Just another reason to have aloe in our yards