The be quiet! Straight Power 12 1000W wins in 4 out of 9 comparable specs, with 3 ties. Its biggest advantage is Wattage (33% better).
MPG A750G PCIE5 wins in 2 specs (MSRP: 42% better).
Recommendation
Choose Straight Power 12 1000W if you want the best overall performance — especially wattage.
Choose MPG A750G PCIE5 if msrp matters more to you.