The only real benefit that I can see is that it will force some states, (California and Illinois specifically), to actually have legal concealed weapon holders active in their populations even though they have specifically refused to allow their own citizens to exercise their rights.
California is a "may issue" state, (which means that only those VERY politically connected with lots and lots of money will ever be considered for a permit). Illinois, on the other hand, is the only state out of 50 that does not allow for ANY type of concealed carry that I am aware of. The state of Illinois does not even bother with the blatantly false "lip service" to allowing this basic human right to self defense as they do in California, (which is in direct contradiction to the latest Supreme Court rulings on the subject).
If this bill passes, then these states, (and the District of Columbia I believe), would be in the rather ridiculous position where they do not allow their own citizens to carry, but out of state visitors can due to a superceding federal law that crosses state jurisdictional boundaries.
On the one hand, I like that notion as many California residents could apply for and receive a permit from a state such as Utah for example and then use that permit to allow thier concealed carry rights back in California, (in theory anyway, I am sure there would be some legal wrangling around this possibility that will be fought over in the courts).
On the other hand, however, I also have to agree in principle with others who have posted stating that they do not want ANY new law or federal control over this issue since getting the government involved, no matter how well intentioned, is a universal recipe for disaster and meddlesome ninnying.