Obviously the 9cm version should be more comfy, but might the 7cm version be comfy enough? I'm 15st, 5' 11", 80% side-sleeper, 20% back. 9cm is €50 dearer than 7cm, and I've just been spending too much on non-essential stuff lately, so that €50 matters. Need the Exped before HUBB at the end of June.