I grew my beard out for 1 year and 4 months. I started my first day of terminal leave from the Navy and grew it until last November. I just let it grow and I trimmed only the mustache to keep it from curling inside my lip. The beard grew to be about 8" long. It was well recognized and talked about on my school campus. I got a lot of compliments from random people off campus too.
I can only grow a "goatee/vandyke" with any kind of volume. However, my sophomore year in college, my beard would have made Jim "the Anvil" Neihardt tremble in fear. Twelve full inches of Naturally Crimson Goat Beard, baby!