Phantasy Star 1 is easily one of the best experiences I ever had in gaming growing up. Finding Dark Falz's door in that hallway was one of the best feelings my 12 year old self had back in the day, and it basically turned me into a life long gaming addict. That game is so special to me that even just looking at the cover art takes me back to those feelings of adventure and wonder the game provided. I highly doubt somebody playing it today will get that same feeling, as it'll just be another RPG to them, but back when it was released, there was nothing else like it.
I bough the Genesis just for part 2, and it did not disappoint - I would put it on par with the first one. It still provided that sense of adventure and had the badass medieval/sci-fi locales that made the first one so memorable. The Nei scene and the ending made it worth all the grinding, and the music, even to this day, is top class.
PS3 is shit, so no need to go there.
Having said all that, PS4 is the only one I can still go back to, as it doesn't require the insane levels of grinding commitment, thus making it the most playable. I don't find the locales, ambiance and music to be quite as good as 1 and 2, but it more than makes up for it with likable characters and fun gameplay. It just doesn't feel as epic and mysterious as the first two installments.