There are two entirely different, incompatible types of "regular coffee filters" -- cone filters and basket filters. These, in turn, come in different sizes.
The cone filter for 8-to-12 cup electric coffeemakers is labeled #4.
The basket filter for 8-to-12 cup electric coffeemakers is labeled "8-12 cup."
I prefer cone filters to basket filters because cone filters do a better job evenly extracting flavor. Also, cone filters are less likely to collapse or overflow, reducing the chance of grounds getting into the coffee.
I prefer paper filters (preferably unbleached) to permanent filters because paper filters do a better job removing bitter sediment.
Of course, when staying at DVC resorts, we don't have choice. The filter has to fit the coffeemaker. So we bring "8-12 cup" unbleached paper basket filters. We bring the same package of filters year after year.