I used 50mm Conduit with Flex where I ended up comming up through the wall cavity, 2 Conduits were used 1 for the RF and Cat5 the other for the Spearker and AV cables from the Equipment to speakers and TV. These were installed from each of the 4 corners of the living room and the one for the speaker & AV cables go to an area under the stairs (closet) where I can swap the way I want the room around. The CAT5 and RF go direct to my riser which is made up of 4 off 500 conduit.
I dont leave a pull cord as I use the inner fibre glass rod of optical fibre cable as a draw wire. Now if you see anyone at the side of the road splicing Fibre cable ask them for a scrap piece and stirp it down, cheaper than those pull rods you buy, and there great for going up walls too.
The above way of running cables gives you great flexibility for future needs
Guy