Looks ok to me, dimm1 and dimm3 are one pair and dimm2 and dimm4 too. The system will run at the speed of the slowest pair, 1333MHz in your scenario. The only thing that can screw it up is, dimm1 and dimm3 don't have a so called KIT pair (2 exact the same modules). It's advised to use kit pairs for best compatibility.
When you use 4 slots, it's always advised to use dimm1 and dimm3 for one pair, and dimm 2 and dimm4 for the other pair, you only have one pair and 2 different modules.