Another problem when most people get all of this balancing done is they just do the rotating assembly and never touch the flywheel or flex plate and converter and harmonic balancer when in reality everything connected to the crank needs to be balanced together. Or that balancing money was more than likely a total waste.
Unless a person is making a serious effort towards the nationals there is no reason to get tied up in $10,000 because your forged pistons are going to where the block out in around maybe 30,000 mile being optimistic.
Depends on what level of performance/goals you are building for
The good news is 318’s and 340's have excellent rod/stroke ratios