Every time I've seen an asphalt floor in a building, it reminded me of Sanford and Son. I never seen one on that show, but they all have a very junky look to them. They never seem to hold up very well and I'm not sure why. I never dented a road when changing a flat, and I never seen a road that would be easy to roll things around on or work on, so I don't understand why so many driveways and covered areas that are asphalt. Maybe it's because the affordable option means they cut too many corners and the results end up that way?
Concrete is the best option by far. It lasts forever and you will never regret having it. If it's too expensive to do now, wait until you have enough to do it. I've never regretted spending the extra money for quality, and I've always regretted saving a buck for something that I knew wasn't the best option available.
Eddie