How much weed you need depends on three factors, the person smoking it, the weed being smoked and by what method. No one can tell you how much you need, just try it and find out. It won't hurt you.

Bongs supply cleaner hits, meaning you get more of the "good" smoke and less of the bad shit in the smoke. I prefer bongs, and if you know what you are doing you can make your own bongs, ones that you don't have to worry about them breaking or spilling or whatnot because of superior design.

I need a digital camera, so I can show you my design.