Engine dilema.. 318 or 360?

So does anything ever go as planned when restoring/building a car?

I had bought and built a 318 a few years ago, nothing special, bored .40 over, crane cam, stock heads. I also have a set of stock 360 heads that I was going to put on after getting them machined etc. Well now I have found a 360 with J heads that I am picking up tomorrow. Lets just say for the price I couldn't pass it up. With that in mind, and also know that I am not an engine guru by any means, would you rather run a 318 as described above, or would I be better off with a stock 360 with J heads, maybe put a cam in it? I know there are so many factors to consider, the 318 is a fresh rebuild, while the 360 has about 20k on it. Or I could put the J heads on the 318 and save the 360 and start building that for future use. I'm starting to realize I have way to many parts now..

As always, any input, advice, opinions or just plain sarcastic slander is greatly appreciated!