As your permanent library ? The quality control is too frustrating, and you rob yourself of the joy of holding a real "album." The paper versions from Salvat’s "Colección Novela Gráfica" are inexpensive and look beautiful on a shelf.
Instead of hunting shady PDFs, check your local library’s digital app (e.g., Libby or eBiblio in Spain). Many libraries offer official Lucky Luke e-comics in Spanish for free, legally, with perfect quality. Descargar Lucky Luke Pdf Espanol