It is going to depend on your experience with both types of handguns. If your experience is less then great, you should stick with a revolver that has less chance of problems dealing with reliability and possible accidental discharges.
My personal favorite that I carry concealed is a Colt Defender 1911 in 45 ACP. Small in size compared to a full size 1911 and lightweight.
When I started law enforcement in the mid 70's most officers carried revolvers and they had to have a score of 70% to preform their duties. My dept. allowed officers to switch to semi auto only if they could demonstrate three scores of 90% or better with the semi auto as the dept felt the auto was for more experienced gun handlers. We did not have the rate of accidental discharges that we heard about with other depts. when they switched because of that requirement.
I prefer the semi auto, but I would not feel under gunned with packing a good revolver and have done so on occasion. Unlike a cop, a citizen has very little chance of getting into a long gun battle with several suspects that would require more then 6 rounds to finish the fight. That event is even very rare for gunfights involving cops as the average rounds fired was 5 rounds by both sides when I retired from law enforcement in 2003.
Get what you feel comfortable with and make sure you practice enough with it to feel confident in your ability to win a gun fight if it ever happens to you. If you have a local IDPA club and range, join it and get the experience you need while having fun doing it shooting against others in your level of experience.
RELH