I like using Live View to manual focus when I've got my camera on a tripod. Really get consistent excellent results. (I have good reading glasses - got a reading prescription in the bottom of my sunglasses - highly recommend it to those over 50).
I considered getting a split screen - miss it from the days of film when I only had manual focus - but it would void the warranty. My D700 is out of warranty now though so I may look into it. Any suggestions on where to get one for a Nikon - and if the lens does the focusing rather than the camera as in the good old days, how does it work?