Sealant products are different than fix-a-flat. Fix-a-flat almost looks like a foam. I just recommend avoiding them when possible because I've seen damaged tires.
Put your spare on and bring the tire in to get patched and plugged. A proper patch is done when the tire is unmounted and pulled from the inside of the tire out. The ones I like are metal and are great for heavy duty use. Mostly because of the mess it makes inside the tire/rim combo that sucks to deal with for the tire people. Consider it an emergency/last resort option only.
If they just plugged the tire from the outside without removing it that's not really a "proper" fix either. A permanent tire repair has both a plug in the hole and a patch on on the inside.
Fix a flat can't eat aluminum, or paint, it's chemically impossible.
It's also going to be very, very difficult for it to get past the bead to the sealing area even if it could. And on top of that, even if that area is damaged, the rim isn't ruined, as any proper tire shop will have sealer for this area anyways.
It doesn't adhere to the tire - and any that has managed to dry on can come off with some varsol and water.
Obviously, if you don't have a spare, use what you've got. AAA membership is cheap too, and worth every penny if you use it once every few years.
I really hate to go unless I absolutely have to, I've had a couple of tires plugged at Wal-Mart and the last time they only charged me $8 which was fine by me. I had a flat and took it to a Discount Tire where they fixed it for absolutely free. I had my debit card out, ready to pay and everything. I just assumed they felt bad for me
I'd had all four tires replaced in the last year and I don't drive much. There's a lot of construction in my town and I ran over a nail.
The nail went right in the middle groove of my front right tire so I knew it could be repaired.
I brought my flat in and the auto repair manager told me to take a walk around the store while his guys evaluated it. An hour later, they call me back and he says it's not repairable and that I needed to buy four new tires.
I told him to take the car down and put the spare back on they'd already put it up on the lifts and he gave me a hard time about it, trying to charge me a couple of bogus fees, telling me my life was in danger if I kept driving on the tires, etc. He finally agreed to do as I asked.
When I went outside, the guys who worked in the garage said, "So,we fixing your tire now or what?" When I told them the manager told me it wasn't repairable, they both looked really confused, then really annoyed.
I took the car down the street to Discount Tire, Co. and they fixed it in ten minutes and didn't charge me a dime.