I'll be the first to say it
search
to be honest there is a thread lower down this page, or page 2 that discusses long arms, which includes 3/4 link and the benefits of each. or a simple search will yield plenty of reading, heck even at the bottom left of this page there are "similar threads" which will have some information, and each of those will have "similar threads" in the bottom left corner of the page... and so on and so on.
you'll also want to say what you want the long arms for too, rock crawling, mudding, better ride after a lift? how much lift its going on... etc etc.