Then I definitely recommend some sort of magnetic storage. You get higher storage density because the minis can sit closer together, and no wear-and-tear from rubbing against the foam (which isn't a problem short-term, but I have lost some paint over years of use on some minis). The higher storage density also means cheaper storage, whether you're making your own with sheet steel glued into plastic or cardboard boxes, or purchasing a case. Finally, magnetic storage makes it easier to show off your minis because they're not nestled in foam.
The one downside is that if the case gets dropped you get catastrophic failure--with foam, everything takes a hit but you don't get minis bouncing off other minis. So if you do air travel, go foam; if you don't, magnetic storage is fine if you buckle the case into a seat in your car.