My gun purchases go one of two ways:
1. I meticulously research exactly what I want. I spend time with the gun, borrowing it from a friend or renting it, learning as much as I can about it and deciding how I want to carry it, what type of ammo I want to carry in it, doing drills, learning how to take it down, etc. I know every inch of the gun before I make the purchase. I order it online or call a bunch of gun stores asking for exactly what I want by name. When I go pick it up, I will know if they hand me the wrong thing, or if they left something out of the box (I've had several experiences where shops have left out a cleaning rod, a speed loader, or in one case even a spare magazine). I inspect it thoroughly before leaving the shop. In one case, I had the gun shop send it to the manufacturer for repair before I agreed to take it.
2. I walk into the gun store to grab a box of ammo or just bullshit with the guys, and I impulsively purchase something that caught my eye that I don't know much about. If I end up disliking it, that's my problem. "Problem" is a bit of a misnomer though… one more gun is one more gun, and you can't buy the "wrong" gun if there's no "right" gun in the first place.
Btw I love my Phantom and prefer it to the Tactical. The Phantom points more naturally, and since both models are more than heavy enough to handle 9mm's recoil, I'd rather save the weight