Be very careful of your expectations when you go into the adoption process. You will almost certainly not get the "warm fuzzies" most imply when marketing the area. A few are open and honest about the challenges, but even those tend to gloss over the deep pain that may be involved.
This is often done with the stupid remark that you don't have guarantees with children you give birth to either. While that is true, it ignores a significant part of the issues involved.
I am certainly colored by our experience, but that doesn't negate the point - You will always have to compete, outwardly or not, with another family that your child(ren) were at least once a part of. Even an infant will have had months in the birthmother's body, so develops some kind of attachment.
The questions of "what if" can also easily plague adopted children, as they do with all of us. They may have to struggle with thoughts of how their life would be different if they could have lived "forever" with their birth parents. Fair or not, this is a powerful area to consider.
The best that happens may be that you give them a better childhood than they would have had. Is that enough for you?