Best / Cheapest Heads for 5.9 Magnum

Yea, but those are still an OEM casting...prone to cracking. The EQ replacements (and the like RHS/Indy X heads) are a much better casting and outflow the OEM's for similar money. That makes them a no brainer...

You asked for cheap.
Most mag heads are cracked between the valve seats, usually on the end.
I have not seen one yet that leaked water.
This guy made a fortune welding up late 80's al ford escort heads and re-sellling them.
He knows what he is doing, but only sells stock heads.