I've decided to buy the colored squares. However to save $100 I'm getting the 20 squares instead of 30. I have 21 students this year, usually no more than 23 any other year. I figure that if my couch is at the back of the carpet then each day a different group sits there. Then there will be enough squares.
To answer one poster's question, yes my school will buy it, I have a $400 classroom budget and we did a class fundraiser and now I have an additional $800 to spend on "extras." It's wonderful! I also bought 2 industrial pencil sharpeners for $100 each and spent $200 on new games.