Easy. It's small and straight forward with a couple open areas to maneuver easily. It also has a low buyable ending which is easily achieved.
It's a small map and there are a few areas that you pretty much stay in the entire time.
Overall it has a good look to it and everything seems to blend. It has a traditional look that works.
Because it's a smaller map you do have some higher paced action. Sometimes simple and small works out and I think it does with this map. Because the ending amount is low enough, it will be a quick game which works good because of the size of the map. You're not stuck in one spot grinding out points to finish. So I think that helps keep the pace of the map so you don't get bored. There can be some tight looping if you wanna stretch your legs and run. Especially with more people you can feel a loss of space and maneuverability which gives the map a consistent high paced feel.
It was fun for what it was. I never felt bored or relaxed. I think the low ending amount worked well with the size of the map and kept you moving quickly to finish.
I would play it once to check it out. It may not have a ton of replay value, but if you only had 30 minutes maybe an hour to play, this would be a perfect map to get a zombie fix for the day.