Tonneau covers are great - but you can't fit a sofa or a bed under it! What do you do when you have a bigger than bed load? Use a Bedder Cover - it will fit on any size truck with any size load. Just like plastic wrap on those leftovers, just keep wrapping until it is covered. The key is to wrap it in such a way that you keep the wind flowing over it - and not under it. Just wrap smart!
My sister recently moved to Ft. Lauderdale from Jacksonville - she had the movers load up all kinds of stuff in the back of her husband's Ram truck. Then we spent a half an hour covering it with a Bedder Cover. It made the 5 hour trip down I-95 with no problems!