No worries, we all have to advise on our own experience
If you buy a pot grown rose now, it will probably just be a bare-root rose potted up in compost just a few days ago. It will not have made much, if any, root growth inside the pot. I bought one like that years ago - I'd paid £s more just for a couple of handfuls of dried compost and a pot
So IMO if you are buying
right now, you might just as well buy a cheaper, bare root one (if you can still find one) with lower postage costs, and plant it yourself where it will grow.
Stock bought later, in summer, will actually have grown roots in the compost, as well as some top-growth, so will successfully transplant at that stage, like any potted plant.
Does that make sense?