I ended up getting an Undercover Ultra Flex for mine on labor day.
NOT MY PIC:
Looks great, keeps 99% of the water out of the bed, installs into the utilitrac rails (you can order this cover for a truck without utilitrac - you just have to specify). It's heavy - box was 80lbs or so. The thing is, the cleats that come with the truck's utilitrac system will no longer be usable on the upper rails. If I had to buy all over again, I would buy the BAK Revolver X4, as they have you flip the rails on the utilitrac so you may still make use of the system.
I bought a bed mat to go with it, and I've safely carried luggage for 5 bros on a bachelor party trip, my drums, my hockey gear, and my picnic/halloween gear for the kids so easily and without worry of someone stealing something out of the bed. I have the largest trunk I've ever had at this point! I recommend this cover if you don't have utilitrac as you won't lose functionality and the look and effectiveness of the cover is top shelf. If you do have utilitrac, maybe check the BAK revolver, but I have only used my system once in a year, and I can get by as 99.9% of my bed use won't require it.