I always recommend people to get their permit when asked. Having a permit does not mean that you have to carry, but it does give you the option should you decide to. Of course this assumes that you are in a state that requires you to have a permit to carry concealed, or visiting a state that recognizes the permit from your home state or whatever state you are planning on getting a permit from.
Having the permit gives you options that you would not otherwise have. I like options.
As to your question regarding the best concealed carry weapon... That is a much more personal, and difficult, question to me. It depends on what you shoot best, what you are most comfortable with, what you will carry and not just leave at home because it is too big, too heavy, too small, too light, wrong color or whatever. A Concealed Carry Weapon does you no good if you do not have it with you, or if you can not hit what you are aiming at, when you need it.
In any case, whatever you decide, I strongly recommend training and practice regardless of how much you do, or don't, carry. If you are not well versed with firearms, start with basic safety and familiarization. The NRA Pistol course is a good one for this. But, don't stop there. There are many good training facilities and instructors out there and the more training and practice you get the better you will be at handling yourself and your firearm whether it be at the range or in an emergency situation.
Best of luck to you