Played all of them except for the PC98 version (for the lack of the actual hardware).
I'm basically to Policenauts what CVXfreak is to Resident Evil.
Breaks my heart that there is basically no translation of it anywhere. There was a group working on translating the PC98 version, and junkerhq.net is still trying to decode the character set for the Saturn and PS version last I checked.
Of all those Japan-only gems in line, this one is begging to get the fan translation treatment at the very least. I don't think we'll see an official one anytime soon, sadly, since Kojima basically burned out on it (yes, the man had already burned out on something else before metal gear came along in full force), and it's reportedly his baby (won't let anyone else direct it, so it would have to be him on the project).