We went through 5 training sessions with our 4-1/2month old English mastiff.
Both my husband and I were a little nervous going into it. The trainers always made sure we were comfortable with what was going on and explained things extremely well. Our pup loves going there and we get complaints wherever we may be on how well behaved our pup is. Our pup is so confident in herself after going through training!
I would highly recommend bringing your pup to sit means sit. They are awesome and work so well with the pups and owners!