Oh, please, the Warthog is proof that speed isn't everything. As long as it can reduce a convoy to a pile of steel mush in less than a second, it's a-okay.
In the interest of fairness the Me-263 is like a patrol boat. Fast but not that armed or armored. The A-10 is like a destroyer. Not that fast but is a literal tank.
Me-262 A-1
Designed: 1937
Maiden flight: April 18, 1941
Length: 34 ft 9 in
Wingspan: 41 ft
Weight: 15,720
Country of origin: Germany
Gun: 50mm cannon
Engine: Junkers Jumo 004
Role: Attack
Type: Jet
Speed: 540 mph; A-10C
Designed: 1960s
Maiden flight: May 10, 1972
Length: 53 ft
Wingspan 58 ft
Weight: 24,960 lbs
Country of origin: US
Gun: 30mm GAU-8 Avenger cannon
Engine: General Electric TF34
Role: Attack
Type: Jet
Speed: 439mph