Has John Lewis Renoir had it?

Amazing information--so helpful and informative. Can i ask how you tell if your mattress has "had it" ours is a John Lewis Renoir bought feb 2006 but looks bit lumpy, we do turn it, but there are the weight difference issues you mention on other posts as my husband is 15 stone and I am 9 stone. Also do toppers make a bed feel hot in summer months?

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