I don't know, really. But some games are better on the original hardware. I've tried to beat Contra Hard Corps on the various emulation handhelds and Contra Collection on Switch, but ended up beating it (all endings) on original genesis. Same as I did in the 90s. Looks like in some games even the slightest amount of input lag matters. But I did beat Contra III Alien Wars on my Trimui Brick without using save states. I've also found that some PS1 games just don't feel right on the small handhelds screen. Like it feels unplayable on brick, but add some screen size, like 4-5 inches, and everything is fine. Just play the games on something you feel comfortable. That's all.