The lyrics and pace of Horsemen are bad ass. The lyrics and pacing of (even Megadeth's version of) Mechanix, is trash. Not even close. I will always be glad that Metallica remade Horsemen into what it is.
Mechanix (Megadeth ver.) is a product of its time. Bitter Dave trying to outshine Metallica by being faster and louder got in the way of groove and pacing