It isn't if the 340 is faster, because we all prefer the 340 if both are free. It's about you having 3k to spend and you don't have a motor. Is the 318 (members claim good running 318's are free) a better choice if performance is your only goal. Will 3k put into a 318 beat a 340 that you had to spend 1500 to get and only 1500 to put into it. That's the point. On a low budget, is the 318 the better choice for your lowest ET .... It has NOTHING to do with "318 just to be different".
