Training method depends largely on the owner. When I was choosing a puppy class I picked one that used treats and positive reinforcement, but that isn't why I chose that particular trainer. I chose him because he also taught proper correction techniques. When I looked into PetsMart they didn't offer that information in their classes. Perhaps that has changed now.
I agree with everyone that you need to spend some time observing the trainer you are considering in action.
Don't pick a trainer for your dog. Pick a trainer for you.
"He is your friend, your partner, your defender, your dog. You are his life, his love, his leader. He will be yours, faithful and true, to the last beat of his heart. You owe it to him to be worthy of such devotion."