It all depends on what you are training.
OD on a tall player trains very slow.
One on One trains very fast no matter the height.
It depends on what you want. Do you want a player that can be a starter quickly? So you train him on either guard or big skills exclusively. Do you want a player that will stay low salary and be efficient even though it may take years to be a starter? You train him in a balanced method.
Overall pops will happen. I don't think it matters too much the number you get. Just look at the player you are striving for in the long-run.
Unless he is super high potential. Then you may just want to maximize pops. But if he's middling potential its more important to look at what he can do for your team.