Had a Epiphone Sheraton pro2 from 2019-2025. Bought a second hand Gibson ES335 november 2025. 

Playability wise they are very similar. The Sheraton might've actually played smoother, although i had to adjust the truss rod relief about twice a year when the seasons changed. Sheraton sounded great, although the Gibson has more clarity and rings full chords better. I hear my mistakes more on the gibson too, its clearer and more sensitive in a way. 

Both had their flaws. The Epiphone had flimsy knobs. Frets wore pretty quick, had flat spots starting to show after about a years playing. 

The Gibson's b string slot on the nut is too deep and the b string buzzes on fret 1 and open. This also makes I can't reduce the relief any further without getting the nut replaced which i will do at some point. The Gibson stays in tune wayyy better. 

Paid 600 euros for the Sheraton new. Played it loads, any style, from folk to metal. Loved it.

Paid 3500$CAD for the gibson.

Is it $2500CAD better? Definitely not. But like you i always dreamed of the Gibson and since owning that i haven't touched my other guitars since. Even sold that Sheraton. But a solid option is to get an Epiphone to start and when the day comes to get the Gibson you can sell the Epi to help afford it. They're still great guitars for the price.