I played the original on psx back in the day and loved the controls. I was wondering if anyone could confirm if this game had gamepad support or if it was just keyboard only.

Works with gamepad just fine. Tried it out meself and it's all well, after you map the controls yourself from within the game. Go DirectInput !
Well, I did this with the Steam version of it, but really, there should hardly be any difference over this aspect between the Steam and GOG releases.

that's great to hear. now I've got another game to buy :)

As Phoboss had already mentioned, you can change the controller preferences through the options screen. I just checked GOG version and yes, it's the same as Steam, in which you can play it with a controller.