I think 32 inch is good if the viewing distance is less than the length of a bed. I think that the extra design of the V4000 might also be worth the extra if the difference is around the £100 mark. Other than that, unless he is into tvs, the L4000 is basically the exact same television as the 40v4000, but just a less fancy design and one less HDMI port (2).
I have a 40" w4500 that handles SD really well, it is about 3/4 ft away from the end of bed and i only just get away with it. so 40" in his case may be a bit of a push. Its quite a difficult question, as 40" screen really does make a difference to films/games.
Can he move his room around to make it so the TV is at a greater viewing distance?