I like the PSP go but it’s mostly useful for fast switching between TV out and portable play. On its own it is fairly uncomfortable with a bad analog and small buttons. But when you can just grab and go to transfer from TV to portable it’s a lot more acceptable, especially when you can easily transfer saves to a more comfortable system when needed.
Yeah you can still transfer games from PS3.
Vs Vita personally I’d rather run PSP games on a real PSP. There are ways to make the video output on Vita look better if you hack it (weirdly adding scanlines helps a LOT) but even then I don’t 100% trust the emulated solution on Vita even if compatibility is very good.
For PS1 games though I’ve found Vita much better as the screen is better able to scale PS1 games to correct aspect ratio due to being higher res as PS1 games can be 256, 320, 384, 512, or 640 pixels wide (maybe more) all intended to be run at 4:3, and none of the 1:1 pixel modes deliver a correct aspect ratio without correction. Beyond that I’ve run into more than a few incompatibilities with non-PSN PS1 games on PSP where Vita seems to have smoothed out a lot of those issues. But of course Via can’t do TV-out on its own, and the PSTV’s PS1 handling is not great due to being very blurry.
240p-out on PSP go is only available for PS1 games; the output isn’t boxed it’s fullscreen.
For PSP games (assuming 480p) the games are output a 480x272 frame in the center of the screen which absolutely requires correction as it will output pixels at 10:11 PAR (assuming the video frame is 4:3) rather than 1:1 so you at least need to stretch it horizontally 10% but ideally scale to fill the screen. On my OSSC the result looks pretty good on an HDTV either by correcting the horizontal res using OSSC settings or better still HDTV scaling settings.
The big problem is PSP go AV out goes through the same port as the charge port, so even if you buy cables you can’t charge at the same time without the cradle which is getting stupidly expensive.
Overall I can recommend it if you can get a cradle for a good price but yeah good luck with that.