Help!

The Legion Go is on sale for $549 right now at Best Buy, and currently the only gaming system I have, is a PS5. I wanna be able to play my Steam games I have; since my laptop kind of died on me, and I know the ROG Ally is good, I can't decide between the two? Right now; the Legion Go is cheaper; and ideally, I'd hook up a monitor & keyboard / mouse to it to use as a "gaming pc" until I'm able to get one. But, is there anything noteworthy about it? Good or bad? I don't care about size whatsoever. I've been sitting on it for a minute, watched a few videos; but just can't pick between the two. Any info would be greatly appreciated! (the games i wanna play via steam are repo, palworld, lethal company, COD, phasmo, hogwarts legacy, etc games that i have in my library basically). And I guess another question to add, would I be able to download mods for repo & lethal company? Thank you!!!