The 360 will give you more torque and more power if the pistons are swapped out to raise the compression up to where the original 340s were. The 340s have the reputation because they came with high compression, big valves, and the better exhaust manifolds. But when the two engines are set up the same the 360 will outperform the 340 every time and make more power and torque at a lower rpm to boot.
Yes being able to say you have a 340 is cool. And if that is what the OP wants and is willing to pay extra to get the 340 by all means go buy one. But it will need more cam and have to be rev'ed higher to get the same power as the longer stroke 360 would and cost more money up front to purchase. More money for less power sounds like the hot ticket to me...