Resp:
From everything I've read, the P-47 was a lot more rugged than the P-51. The US 8th AF lost a lot of P-47s in air-to-air engagements in the beginning for several reasons; outdated training, lack of experience . . . due to coming into the war late. Tactics took time to develope. There are many stories of P-47 pilots returning to base with aircraft so badly damaged . . . the aircraft were written off. The P-51 gave a pilot, especially an experienced pilot, significantly better manuverabilty against the Luftwaffe. Range brought them into areas the P-47 couldn't tread until the Allies bases advanced across Europe.
NO it was not a lot more rugged than the Mustang.
It had critical faults such as bursting into flames being hit in the engine and hitting the Oil Cooler and Tank.
May have been able to escape small arms fire but the Germans were tossing 20mm, 30mm and 40mm AAA.
All the German planes had 20mm cannon that would make short work of any fighter.
The only thing going for the Thunderbolt was a fast dive with a decent Mach number, decent zoom, great roll.
But pathetic Climb, Fuel Economy and Needed a slight dive to get to decent level speed.
It was not a very aerodynamic plane.
They were not that well protected with lots of oil lines going to the Turbo, tank and cooler.
Hit any of them the Turbo overheated and oil flaming.
Corsair had the same problem.
When the P51 B/C/D arrived the Luftwaffe was at its peak and the Thunderbolt could not get to the fight.
Had to wait until the Bombers returned where they picked up the escort.
Or they lead them out with the Mustangs picking them up.
For all the Performance of the M had - Thunderbolt it fought under 20k Feet.
It really never was flown as an high altitude fighter at the time.
Then again the M's 2800 P&W was very problematic only in combat a couple months.
Still the Mustang was faster, better climb more maneuverable.
It was not until the P72 with the P&W 4360 or the Hemi Chrysler V16 that the Thunderbolt came alive.
Now if the Thunderbolt like the N model which used twice the fuel of a Mustang they could shoot down a few planes.
Short-Medium range the Thunderbolt was great.