When reviewing portfolios, I prefer a weblink or a pdf. Personally I find ISSUUs interface and lag a real pain, I wouldn’t use it.
When interviewing someone, we always have a projector ready to go so the person can project from a laptop or show printed examples. A personal pet peeve that I notice happing a lot lately is when candidates come in with nothing more than is on their website or in the sample PDF they sent. I’ve seen that already. That got you in the door. Now you have to blow me away to get the job. When I interviewed as a young design I would try to bring enough to annihilate people and then some. If an interview goes well, it will usually run long. Have enough to keep it going.