Not to be deliberately difficult but surely "I like Rachmaninoff very much" is a different statement than "Rachmaninoff is a radical"? There's surely plenty of pieces where nobody would even begin to argue that they were radical (even in their time) that can send chills down one's spine.

(The counter-argument might easily descend into "all great art is radical" I suppose the article itself touches on this: "At these colloquies, someone inevitably proposes that Composer X is more of a modernist than had hitherto been suspected." As a huge fan of the Vaughan Williams symphonies, I'm rather familiar with this trope)

A common story about the piece is that Rachmaninoff took inspiration from a dream he had. The dream was set in a funeral (hence the bell-like tolling at the beginning of the piece). As the dream progresses, Rachmaninoff walks toward the central coffin, and the piece builds suspense as Rachmaninoff continues to get closer. When he finally gets there, he opens the coffin only to find himself inside, coinciding with the beginning of the climax of the piece (marked "agitato" on the score). Whether or not this story is true, or painted on to the piece at a later date, the story seems to match the progression of the piece.

(copy pasted from Wikipedia but very interesting nonetheless)

Other great tracks:

Prelude in G minor, Op. 23, No. 5.

Piano Concerto 2. It's long but at least listen to the first 30 seconds, up until the point when the orchestra comes in. This is (in my opinion) one of the greatest moments in all of Western art music.

I would also recommend Khatia Buniatishvili's.

Obligatory https://www.youtube.com/watch?v=ifKKlhYF53w

His version of the B Minor prelude gives me that chill every time. Glad to see another fan.

Wonderful piece.