Re: AR-15 lower or a handgun
If you buy the AR lower, it may be a while before you get to put it together and shoot it. If you buy the handgun, you can go "Bang, Bang!" right away. I dont know what your financial situatiuon is like, or what(if any) guns you have already.
If you have the $ or patience to build an AR, and you already gave a handgun, go with the lower. If you have other rifles, and a shortage of handguns, get the handgun.
Also, I dont know if you have/need a permit where you live.
Where I live, You have to take your class, get fingerprinted,submit your paperwork, and sometimes wait 2-3 monthsto even get a temp. permit. If that was the case, I might start with the build, since you might have it finished before you get your permit.