Seems a real shame that ram lambs are considered as such a disposable commodity. I personally prefer to keep a good ram for a couple of seasons, longer if I don't keep back any ewe lambs. A good stock ram will usually sell for a good price at a breed sale too once his job is done for a flock and it is necessary to move him on. If a ram lamb produces some good offspring and you have the room to split him away from the ewes as necessary, I think this is much less hassle than having to find another suitable ram the following season. In addition, constantly changing a ram brings in the risk of diseases etc from the purchase venue. Only my very humble opinion though.