Honestly, I think leaving them on is a good choice! Everybody takes these things off now a days, and I find it refreshing to see them on. I also don't know why someone would want to paint them or even paint over the chrome bumpers?? Sure it looks great at first, but the paint always chips, and in my opinion looks worse once the chipping starts. I wouldn't take them off, unless you had something to replace them, as someone else said, it makes the truck look more like a base model. Another good choice would be to maybe get some of the Extend-Fenders from Bushwacker, and get them color matched. I've been toying with this idea for a couple of years now, but haven't pulled the trigger yet. The only thing about that though, as someone else said, it kinda looks goofy if you don't have bigger wheels and tires.
These are just my 2 cents, and most likely not the most popular opinion, but that's me, I never go with the popular vote! Either way, you have yourself a nice rig, enjoy it!