I've had the ally gators on my 21" wheels for over a year. To be blunt I hate them. They look great when you first put them on but it's all downhill from there. Mine were installed by an expert so don't tell me it's the installation. They come loose from under the tires, they collect dirt, and over time they don't lie flat against the rim in places (what I call a ripple effect). And they're incredibly difficult to remove even when they seem to be falling off the rim. In short they're ugly, impratical spunks. Observant people notice and ask me what's wrong with my rims. That's exactly what they're supposed to prevent -- looking like your rims are damaged. After a year of wear and tear (and two replacements) these things make all of my rims look damaged to one degree or another.
I know people are going to say they look ugly because they protected my rims, but there's got to be a better product that serves that purpose. One that's easier to put on and remove when they're damaged. The alloy gators are a pia to install and remove.
So they're coming off this week, to be replaced by something else, yet to be determined. Regrettably I have to take them to a tire shop to have them removed. Being the DIY guy I am, I tried to do it myself today -- jacked up one wheel, let all of the air out of the tire, and still couldn't remove it.
I'm sorry I spent a dime on these things.
I'll post some pictures when they're removed so all can see how ugly they've become after a year.