Codescape is one of the better escape rooms I've been to. I played "The Residents" with one other person (I believe the room is recommended for up to 8 players.) Personally, I wouldn't recommend a group larger than four because the room is on the smallish side and even with just two of us, we were constantly in each other's way or standing in front of the light. I think a couple of the puzzles could use some tweaking, as I felt there were minor design flaws that made otherwise fun and clever puzzles needlessly frustrating. On the whole, it was a good game and I would go back to do their others next time I have the opportunity.
If theme is very important to you, then Codescape is a MUST. The set design was very good and the music and sound effects did an A+ job of setting the tone. I haven't done any other horror escapes to compare it to, but I enjoyed it.