I guess I am getting old fashiobned, but after wrestling with a big block in a B body I was delighted about how easy a small block is to work on in another B body I had for awhile.
Put it this way the 340 requires no modifications to the drivetrain. It will run on your existing linkage, tranny, radiator, wiring, throttle, suspension, etc. A big block will require changes to just about everything mentioned.
Will a 340 out accelerate a 440. On most equal terms yes, but a stroked 340 or even a 360 can be had for the same price and you will save a ton by not having to modify the entire car to slip in a 440 to make up the additional cost for a stroker kit.
I have the same argument with the 383 in my bee. Folks tell me to drop a 440 in and my response is why...I would rather stroke it or drop in a 451 rather than add a ton more nose weight, and make it even more frustrating to change plugs with headers....
Now a HEMI though....