Lets make it easy , 1 1970 340 1 1974 360 both factory fresh , both $1.00 , which you going to take ? Let me guess , you can buy a 360 for -$50.00 . Very simple which is best , not which can be built better or cheaper .
the answer to your stupid argument is the 340 only because they had compression and you could buy off the shelf pistons. the realality though in 2011 is the 360 is a better choice money wise unless you get a 340 cheap. even then i would sell the 340 for a nice profit to some old head guy that thinks he can't live with out a 340 or a resto guy.