I was told you shouldn't hunt them their first year anyways? So might as well have them trained the whole time.
It depends on what you're going to do with them. If they are going to be hunting dogs, might as well get 'em going. They will only learn more about their job. However, if you are planning to run them in field competitions, then you could run into conflicting issues in their training.
Most of ours are for hunting. And most of them hunt at less than a year old.