If you shoot in portrait orientation at all, I would recommend getting an L-Bracket. Once you try one you will not buy another camera plate. I have L-Brackets on 7 of my 8 DSLR's and two of my film bodies. I also have a Kirk Universal L-Bracket that I use with the remaining bodies that just have camera plates.
As for brands, I have both RRS and Kirk L-Brackets, Plates, and Lens feet. They both make excellent quality products. You can't go wrong with either one. Good Luck and Enjoy your Nikons!