Dam. I found this late. Anyone who thinks a slant is close to a teen is nuts! Sorry no offense, but like it was said theres close to 100hp difference.
The next thing i will say is contraversail! Stick with the 318! they can be made to have 400+hp easy. And thats not with alot of money either. There are many good articles that will help you acomplish this. I love the 318, so im bias, The is plenty of hp in them and im a strong believer. 360 more cubes, 360 no replacement for displacement, 360 see my tail lights. lol Dont get me wrong, the 360 is a great motor when built correctly. But ask my buddy about his $4000+ 360 that was just smoked by.......yes a 318!