This is a very subjective question - because a studio in one city can be really different from another. They should all be consistent in quality if they're all the same "brand" but that's not how it is at all.
It just really depends on who is working there and how they are with your kids.
We used JCP for DD's very first pics at 2 mos old (she's now almost 6)....they turned out great.
Then we tried
Walmart a couple times for Fall and Christmas - we LOVE the pictures but had problems w/ them. In the fall pics, the photogs sleeve shows up on one side of our fav prints - this did not show on th eproofs, but did on the actual prints. At Christmas, something happened w/ the negatives and we had to reshoot - the first pics were MUCH better than the 2nd - babies are just unpredictable.
Went through a JCP stretch and ended up getting low quality work there - their photogs just rushed us thru w/o spending any time with us.
Then, we started going to Target. Had a great guy there named Jeremy and we ALWAYS asked for him, because he was so good with our DD. Our best pictures came from Target. Then he left and went to Sears so we followed him there - we went once there and were very pleased.
I haven't been to Target in a couple years - I've heard some negatives about them, but I've heard them about ALL of them! I do know that Target now has the cameras so that they can move all around and do "floor shots" where they can stand over the child and take pics. Gives them a lot more creativity.
There ya have it - we've tried 'em all.