Let me get straight to the point; Shogo is one of the most difficult, frustrating utter bastard of a game I've ever played. Firstly, your health counts for nothing; three shots and your out. The AI has supremely quick reaction times, and there's a hell of a lot of them, and health and armour pick ups are few and far between.
"So why the 4 star review?" I hear you all ask. Well, put simply it's one of the most rewarding FPS games I've played in a long time. Sure, it's hard as nails, and the temptation to smash the keyboard into the screen after being killed for the 32nd time is oh so strong, but if you stick with it, you really do get to like it. Firstly, the kills feel very satisfying(which is something a lot of modern FPS developers seem to forget about), the enemy AI acts brilliantly to be being shot, and there is a hell of a lot of blood. The guns look and feel great also, supremely powerful, and the duel weilding pistols have do havea certain cool factor.
As far as graphics are concerned, it has aged really well. Dont get me wrong, it isn't stunning, but not once did I think "oh I wish the graphics were better. It sounds great too, some really natty voice acting, cheesy jap-pop music for the intro, and the guns certainly sound satisfying. Also, a round of appluase is in order for GOG too, as it installed and plays without drama in my vista64 rig.
So, in short, if you're looking for a mercilessly hard sci-fi FPS with badass weapons and an alright plot, it's $6 well spent. Hell, that's less then a pint.