Im not a guy, but I shave my pubic hair.
All of my hair grows back very fast, so I cant say how long it would take to grow back for someone else. But I usually shave my legs everyday, and my pubic hair every 4 or 5 days. I just hate having hair there, so thats the only reason I remove it, not because it looks better or anything.
And the skin down there is VERY sensitive, and using a rough razor on it will make it become itchy and possibly bumpy. The first time you shave it off, it shouldnt be itchy or bumpy. But the more frequently you do it - the more often it will be red and itchy. So dont shave frequently unless you just really want to.
Also, DO NOT EVEN THINK OF USING NAIR DOWN THERE! Or anything similar, it will be hell!! Nair products melt the hair away, and it will sting, burn, and DEFINETLY itch if you do. So be warned.