My question is - do you plan on running at maximum weight all the time? Most of us probably won't, and in some (many?) cases if we did, we would end up exceeding our rated axle limits.
I'm willing to bet you have a 12K rated front axle and 20K rear axle (if not lower). Do the math - that's a max of 6K per front tire (assuming even side-to-side distribution) and 5K per rear tire (same assumption) and it's worth noting these tires very often have different ratings for running single/dual (again, you're unlikely to exceed these ratings).
In my area, the cost difference between the 14 and 16 PR is only a couple bucks, depending on tire brand, model, etc. - I don't buy tires I don't recognize, or get recommendations for. I generally stick with name brands, or tires made by the recognized companies. In your case I believe the 14 PR will be fine.