Cast vs. Forged Crank?

The MP cast is a very good piece. I've seen them live at 600hp, plus 175 shot, raced a dozen times a year at multi-day events and up to 500hp expectations they are more than adequate. But - in terms of "the big picture"... If you're spending thousands now, why wouldn't you spend another $2-300 to get "the best"? I always internally balance, and never have a manufacturer do that work. Don't pay to have them do it, then again to "have it checked". Just pay your shop to do it. External balancing adds stress throughout the crank, not "just the ends". That's where the weight goes, but the whole thing gets stressed. That's how cast cranks get broken at lower hp levels, and in some contributes to why the power figures are never quite right.
So in short - get a forged crank. Do not get it balanced. Also a heads-up if you're sourcing parts yourself - you will need the narrow rod bearings.