Once the Supreme Court decides that the right to bear arms is an individual right, there will be incredible reliance on that fact, individual as well as corporate. Additionally, the language of the amendment, as well as the circumstances leading to it are sufficiently clear that once an interpretation is made, the court could not easily change their position without discrediting themselves, and because the language is so clear it is hard to imagine the evolution of a legal principal undermining this right. So, this would be a very strong case for stare decisis as outlined in Casey and would be hard for liberal courts to attack.
Lastly, the court’s interpretation of the 2nd Amendment would set a minimum amount of protection that the states would be required to give arms. Any future Supreme Court decision reinterpreting the second amendment would reinterpret this minimum, not the maximum amount of protection required. Thus, we would be in the same situation as now, except we would have a minimum level of protection in every state.
But hey, call me a cynic. I've seen the U.S. Supreme Court erode more freedom than grant. The downside to incorporation would be my post #989.