Porch and deck enamel is a durable enamel made specifically for use on surfaces that get heavy traffic. If you decide to paint the concrete, this enamel would be your best bet.
In warmer, humid climates, enamel, or any other kind of paint for concrete, can peel off if the concrete does not have a vapor barrier. Enamel seals the surface. If there is no vapor barrier, water vapor can become trapped under the paint and cause it to bubble or flake off. Remember that paints are coatings, and almost all are opaque.
Since the paint is a covering, attaching itself to the surface of the concrete, it tends to wear away faster than a stain. It’s impossible to give you any specific length of time that paint will last. This is because there are too many variables to consider – such as how much traffic the area will get and what kinds of traffic it will be. Is the surface going to be walked on with hard-soled shoes or with tennis shoes? Will tires be driven across the surface, and will the tires be turning as they roll over the paint?
The advantage of concrete stain is that it does not seal the surface and therefore it allows the concrete to breathe. This means water vapor can move through the surface and isn’t trapped under the stain.
Staining concrete is very much like staining wood. There are different levels of staining. The darkness of a stain depends on the pigment used and on the amount of pigment in suspension in the carrier fluid. The surface will not be opaque like paint. Stain gives a see-through finish like stain on wood does. Stains by their nature penetrate the surface of what they are being applied to; this is true of concrete stain also. Since the stain penetrates rather than just coating the surface, it lasts longer than paint.
Some full-service paint stores have samples of stained concrete to show customers. I would look around and do some talking at your local paint store to get a firsthand look at some of the stains they offer.
If there is a single key to successfully painting or staining concrete, it is preparing the surface properly. Any concrete surface should be cleaned thoroughly before applying anything to it. The best method is to scrub it with muriatic acid. The muriatic acid helps lift stains. Next, pressure-wash the entire area and let it dry completely. Pressure-washing blows away dirt particles, which the acid has put in suspension. Cleaning anything depends on loosening dirt and then rinsing it away.
Once the surface is clean and dry, paint can be applied with a brush or roller. Stain should be applied liberally with a brush or roller and then allowed to stand for a short time so that it can penetrate; then excess stain must be wiped off.