Assuming that the training classes are not outdated in the methods they employ, taking a puppy to training class only helps the puppy in terms of manners and socialization.
Sure, you can practice behaviors at home, but a training class is one of the most distracting yet CONTROLLED environments out there - which makes for a great place to train and proof what your dog knows.
So while I wouldn't say a puppy "needs" training class, I think training class is enormously beneficial.
What do you mean by "professional"? Also, what is your previous experience raising puppies?
In general I'd say that most puppies will benefit immensely from puppy kindergarten (socialization) classes and/or basic obedience classes. A good instructor will clue owners in on how to set boundaries and institute a positive reward-based system. If you are comfortable with this and feel confident that you already know what you're doing, then you might be able to skip these classes. But since you're asking, I'm guessing that isn't the case.