340 Vs 360
I think the differences are very minute and secondary to the important stuff.
If you are stroking it the 340 has a little bit of advantage just because of bigger bore size gives you more cubes. Also probably better flow characteristics.
Stock stroke, but otherwise properly built engines, the 360 will make a better package in most situations. Longer stroke, more torque, more area under the power curve. Emphasis on "most cases".