Visuals: Visuals... visuals, they can be nice and realistic when you're in the games "real world", but when you're using the Dreamwalker... it looks artsy in an abstract way (or... just creepy as hell). Take a bunch of paper and piece together an image and that's what you (kinda sorta) get in the Dreamwalker based on segments gathered by the scans.
Gameplay: As far as the gameplay goes... there isn't much to the controls as far as complexity goes, but the simple controls don't take away from the action or the challenge. The game can be linear, but the developers took advantage of it by adding other elements in there like... deciphering raw data to figure out where in the space it's meant to go. You can also unlock different areas by approaching an area differently (hint hint).
You get bits and pieces of the recreated world based on what was scanned from the brain... and you have to search through that world in order to uncover more areas of the person's mind. You have to solve puzzles, gather clues, and switch between objective and subjective states in order to put things together. The more you fill in the blanks, the clearer the picture is as far as the recreations go... and you end up going deeper which gives you more access to clues that you will put to use in the outside world in order to help progress the case. I'm telling you... it's interesting + eerie.
One con I can give the game... is its stiffness, the animation could be a bit more smooth... but it doesn't affect the experience.
Price: The Signifier comes in at... $19.99 with the Deluxe Edition coming in at only $21.99 ($2 bucks more = just grab the better edition if you want the soundtrack). Solid price for a really interesting experience.