Wether it is 50 or 28 makes no difference. The balancing of the motor is done to the rotating components.
The only thing new where the pistons and flex plate the flex plate was to get the 50oz imbalance on a 157 tooth flex plate for the late model 5.0 HO and use the 70 C4. Don
Just FYI, I bought a new 157 tooth flexplate that was supposed to be 50 oz imbalance for my 5.0 and on first start had a bad shake. My flexplate, balancer and torque converter were all new so lots of possibilities for the source of the problem. By comparing the new flexplate to a 50 oz 164 flexplate I was able to determine that it's balance wasn't right. Replaced the flexplate and the balance problem went away.
If you have the engine balance then you can be sure that the parts are correct. The "imbalance is in the flexplate/flywheel and the front balancer to make up for the imbalance of the crank. Once it is all assembled and the parts balanced as a unit there is no imbalance.
Balancing an engine is not an expense - anymore than buying pistons and bearings. These things are necessary parts of any performance builds.
Right now the only thing I am doing is recovering from a stay in the hospital. What happens this summer is all up in the air.