the best way to obtain the strain/genetics of your desire would be to buy a seedpack from a legit breeder,seedbank.
then mother one of the best females that you liked from the batch,and clone
if you buy clones from the dispensary,where do you think they get them?from the patients.and who knows if they gave them the right genetics/strain..as long as the clones look good they will buy them..they could call it some type of OG just to get it off..
some shops do their own bud growing and cloning,but i still would not trust them personally,they will throw a name on a plant just to sell the clones. and some are stingy with their good phenos and will give you the less appealing ones.
if you buy clones from another patient,atleast try and ask too see the final product first,so you get an idea of the plants genetic/strain/pheno etc.
but like i said,start from seed and you should be more then good,also u have less risk of getting bugs from other grower's rooms on their clones.
EDIT: with one med shop,they told me straight up that they bought their strain "cheesus" from seed and picked out all the good phenos and kept them,the phenos that they didnt like,they still cloned them and are selling them in their shop..
meaning they are selling the patients the phenos that arnt as good.and keeping the good ones for theirself,which doesnt matter because all the bud in their shop wasnt that great to be honest.