Rebel420

Hey all,
My question to you all is, I am new to this mj smoking community, so I am not exactly clarified in all depths of topics relating to mj. I am planning to buy me a new bong, but I am not sure what size to get. I have only smoked once, and that was on a little crappy pipe I borrowed from my friend on thanksgiving, in which I coughed all over the place with. I went to my headshop and saw a couple bongs there. There was a 10" one, which is good to take with me to parties and to stash easier, but there is this 18" bong that im looking at too, which might be too hard on my lungs, I am not sure. The guy at the headshop said that the bigger the bong, the better the high, is this true? Both of these bongs can be filled with ice for killer cold smoke experience. Should I go with the 18" inch bong for 150 or the 10 inch bong for 100 bucks? Any opinions guys? The lungs arent really an issue for me, I can increase my tolerance in no time, what I want...is a bong that will deliver nice, massive hits that will make the most out of my buds.
Keep tokin,
Dexter