Holding it is nice, but the proof is in the shooting. Wider grips spread recoil, reducing the felt recoil and making the gun easier to shoot well. Case in point: My wife decided she'd like a handgun of her own. She held a Ruger LC9, and fell in love with the slim grip. Bought her one, and went to the range. She fired three rounds, and laid it on the bench - too painful. I got a grip sleeve, and she could endure a magazine, but quickly developed a flinch. I went to the rental counter and started bringing 9mm to the line for her, until she'd shot every 9mm in the rental fleet. She was a but more accurate with a G19, but the M&P 9c was the clear winner for comfort. She loves her new 9c, and shoots it very, very well. She'll burn up ammo until she gets tired of loading mags - usually three boxes or so.
I kept the LC9 until I got a G26 - now it's on consignment. Easiest to conceal is nice, but the G26 is far and away a better fit for me. It's a joy to shoot, accurate and very fast.
Get a gun that you enjoy shooting, and shoot it a lot! The 9mm will get the job done, and ammo is considerably cheaper. I carry a G30 (.45acp), but I will be adding the G26 to my permit.