Most the GSP ive come across just lose the plot and run about clearing game from a 5 sq mile area, ( I know there are some good ones but not many). Labrador every time, great companion, good nose, retreive when you want them to and just an all round great dog. I have trained over twenty of these and a similar number of Springer Spaniels and although I have a very soft spot for the spaniels, the Lab comes in front. Buy from a reputable breeder of hunting dogs, ask to see the parents and see them work.
Then resist trying to teach it anything more than sit and come here until it is six months old ( they are only ever like a 2 year old child when mature) then gently build on those basics, like sit and stay and then sit stay come here when called etc etc. If you havent done it before buy one of the books by a top trainer and follow that. The biggest thing is not to treat it like a human and talk its ears off! more than one word is too many for any command and more than two words it will not understand, it will just pick the most familiar word out and do that. Whistle commands are best as they travel a long way and do not disturb all the game around you. I and most others use one sharp peep for stop and a double peep for come here. I could write a load moe but here isn't the place, just buy a good book.
Better the man suspected of being a fool keep his mouth shut, than to open it and remove all doubt.