Where I can't agree with you yet is over whether the Me-262 is impressive.
Seems to me that a fighter which has trouble getting airborne, trouble
staying airborne for more than 25 minutes and which is unable to complete a
turn while over a single county

Hmmmm... can't agree with those statements. It had a far better takeoff
accident rate than the 109 and other than requiring a hard-surfaced runway, the
greatest difficulty in getting airborne was fighting their way through the
Mustangs over their base. As for its flight duration, 25 minutes was nothing
close to their sortie length. Logbooks I have seen suggest that four or five
times that was most common. The last comment, concerning their
maneuverability, is not true - while not as nimble as a P-51 or Yak, its good
to remember that neither of those fine aircraft were as nimble as a Po-2, or a
Sopwith triplane for that matter. When an aircraft possesses a speed advantage
that causes the enemy aircraft to "hang in the air as if motionless", such an
advantage will quite likely cause it to suffer somewhat in other performance
areas. Maneuverability isn't what kills you - that's usually a defensive skill
- its speed that kills. That, and overwhelming numbers!

v/r
Gordon