The Quechua mats Emma and I own and had used without any problems on our Lands End to John O'Groats trip, are by no means the best on the market however reading around it seems like most sleeping mats suffer from delamination. Bearing this in mind we figured we would make use of the mats we currently owned and when they wear out replace them with one of the below.
How has it performed (27/05/2010)? Justin's mat suffered from an air bubble forming inside the mat making it deformed and not comfortable for sleeping, I think this process is called delamination. Luckily the staff at Decathlon in San Sebastian, Spain offered to replace the mat for a brand new one that is slightly lighter and smaller than the previous mat. So far the new mat is comfy and light so Im still happy with the Decathlon brand mat.
How has it performed (30/06/2010)? We are now both using Thermarest Z-Lite mats after Emmas mat developed a few punctures and Justin went through two replacement mats in two weeks we decided it was time for a change. The Z-Lite mats take a bit of getting used to as they are less comfy than an air mattress, they also pack a lot bigger meaning we now store the mats on our rear racks. However the benefits of never having to worry about a puncture and being able to sit on them outside the tent outweigh the size and comfiness issues by far.