The Paderewski Editions are technically not urtext, but are still very highly respected nonetheless. Paderewski gathered a distinguished editorial committee for the project and they examined the manuscripts, autograph copies, original editions and prominent foreign first editions for comparisons. The commentaries in the backs of these volumes are excellent to say the least. Although I do use and like Henle for Beethoven, Schumann, etc., I still prefer the Paderewski Edition for Chopin. There's a lot of scholarship, history, and insights there!