Ive dealt with a lot of epoxy floors and sports cars with very hot tires, and all of the DIY stuff is almost guaranteed to peel at some point (sooner rather than later).
I found a company called Granite Gargage Floors (google them) that was local to my house. They came out to the house, we decided on what I wanted, and they did it! It was cheaper than tile but much more expensive than your DIY epoxy kit. They spend a lot of time prepping the floor before the multiple layers of epoxy go on.
In the end, it turned out amazing. Its very durable, looks like granite!, great texture for good traction on rainy days, and they give a lifetime warranty on the floor. Im very happy I went this route. Everyone that walks into my garage says it's nicer than every room in their entire house.
Here are a few pics.... (floor is kinda muddy in last pic from me parking my Tundra in there
)