I agree with rockaction on Midwestern Songs of the Americas, that album is near-perfect.
I try every couple years to listen to London Calling, and I can never get through it. I actually own it and have tried maybe 20 times in my lifetime, think I've finished t once.
Historical context matters for London Calling. When it was released in late 1979, the initial energy of 1977 had largely run its course. The Sex Pistols had flamed out and post punk/new wave was moving off in a dozen different directions, mostly unrelated to punk. Punk was limited by its self-imposed boundaries and the same revisionist/anti-revisionist arguments that are still present in this thread.
The Clash was always the most ambitious of the UK punk bands. Give 'Em Enough Rope was a flawed attempt at commercializing their sound. London Calling was a much more successful effort at expanding the musical horizons while maintaining punk's ethos and core sound. It signified that punk wasn't dead either as a creative or commercial (by punk standards) force. It inspired a lot of poor imitations but I think it still holds up today.
It was originally programmed as a double LP with four sides. Cramming it all on one CD and listening front to back hurts it IMO.