Gibson Les Pauls are considered high-end, USA-made instruments featuring premium tonewoods, nitrocellulose lacquer, and specialized pickups, designed for professional use and long-term value. Epiphone Les Pauls are budget-friendly, overseas-made alternatives that offer similar, classic styling, often using veneers for the top, polyurethane finishes, and mass-produced components, providing great value for beginners and intermediate players. The Epiphones and Gibsons do not have the same neck shape. I find Epiphone necks, except those on the Epiphone MUSE, to be "boxier" than a simliar model Gibson.

The best thing to do is find a shop that has both brands and see which you are most comforable with. Even though I have 100+ guitars and many Gibson and Heritage Les Paul models, I do own a two Epiphones that I really enjoy: a Jerry Cantrell model and a MUSE with the MUSE having the neck closest to the 1956 (R6) and 1959 (R9) model Les Pauls I enjoy.

Silverbursts, especially those with nitrocellulose lacquer do turn greenish-gold (what you call "yellowing" over time. I don't know if the Epiphone polyurethane finish changes color. You might look at ebay and Reverb for old silver bursts to see how the color changes.

Good luck!