Attend a training class prior to buying anything. It is counterintuitive, but right now you appear to not know what features and details will and will not work for you. For example, I went to class with a stock Browning High Power. It was great on the range but terrible as a defensive firearm out of the box. The magazine well was not beveled and loading magazines was error prone. The slide serrations and indent for the slide release were razor sharp. I bled all over that gun with far too many cuts to my fingers. It carried well, but needed dehorning, night sights, a trigger job and beveled magwell. All this plus refinishing would cost quite a bit of money.
Use what they hand you in class. You will get to know it over the next two days. There will be things you like and dislike. You will be able to apply those lessons to the next gun you look at in the gun store.