That's really a hard call...........guess only you can decided but I think I might go with the breeding the pure labs. It is a very popular dog where I live. You would surely get one out of the litter for you breeding purposes. But at the same time, if the lab/poodle mix is in higher demand, you would be more likely to find good homes for them and you can always find a male to breed your labs with later. May cost you more to breed at that time but if that is truly something you want to do, then just pay a stud fee. I would still to your original plan.