do a lot of new work and old work home theater, cable, dbs, and high speed network systems.
I like the open work method. Run all cables drilled through one inch holes through the top plate or the sill plate centered in the width of the stud and right next to it. If doing new work, use nail on electrical boxes, but cut off the nail holders along with the nails. Cut two 3/8" holes on one side of the box spaced 3 inches apart and 1/2 inch back from the lip. Using a 2 inch hole saw cut 2 inch holes at the top and bottom of the box where the cable entry holes reside. When installing the boxes in new work, drive 1-1/4" dry wall screws through the sides of the plastic boxes into the studs. The reason for this preparation will be clearly seen, if you will ever have to upgrade. Run all of the cables necessary. Apply clips or staples in the attic or in the basement to lightly tension the cables. It is important that the clips or staples are only in areas accessible after the walls and floors are finished. After installing all of the cables, tape the front of the box and all of the cables in place with blue masking tape.
If you never staple the cables onto the studs inside the wall, you will be able to take off the accessable staples and use the existing cables to pull new ones. The side of the studs will also direct push rods and guide any new cables you need to pull.
By preparing the box as stated above, a screwdriver can be used to remove the two dry wall screws holding it to the studs. Since the nail holding protrusions are gone, the box will also come out the front hole in the dry wall without making the hole larger. It can also be easily replaced.