Re: First pistol purchase
Here's my opinion for whatever it's worth. The odds are that you will never have to use your gun against another human being. So based on that, the most shooting you will do is at the range. 9mm ammo is much less expensive than .40 ammo.
If you ever need to use your gun to protect you and your family, the 9mm will do the job. Granted, it doesn't have the stopping power of a .40, but it will definitely do the job.
For home defense ammo, buy good quality home defense rounds and never, never, never use reloads. For me, I use what the local Police department uses (Speer Gold Dot).
So, my vote is for 9mm unless you really want a .40. Good luck in your choice and whatever gun you buy, don't buy cheap junk, buy a quality, proven firearm.