I'm currently doing some alterations to my workshop and will be putting in a block wall and an internal door to divide part off as an office. The choice of block over studded is because I've already got a bricky coming to do some other work and it's easier for him to just put that in while he's at it. Anyway, back to the door. My brother suggested using what I think would be termed a pre-hung door, one that comes already made up and attached to a frame for you to then build around. Does anyone have any experience of these? It seems a reasonable notion as opposed to building the thing up piecemeal after the brick work is in place. Any tips?