So I have a mini-review to give on this guy:
I bought one of the larger (eight x eight) multimats and used it every night for our recent trip down the San Juan. Overall I am very pleased with the purchase. Notes:
The mat was big enough for all 3 of us guys to sprawl out on with and play cards in the middle. Using the small d-rings (12 in all), it's a good idea to stake town the mat so it is taught. The sand falls through the mat better if it is tight, rather than loose. After 5 days of romping and rolling all over the mat I couldn't find any holes or tears. In some places, because of the small bumps in the underlying sand, sometimes sand doesn't fall through that well. In these cases, all you have to do is rub your hand over the spot quickly a few times and the sand works its way through.
The only thing I would do differently next year would be to bring large beach towels to lay on top of the multimat. The material this mat is made out can be very uncomfortable on your ankles if you are sitting indian-style and rough on your elbow if you are supporting your head with you arm while laying out horizontal. A towel underneath your body will buffer this and make it A LOT more comfortable to lay on.
Here are a couple pictures from last week: