The attached graph shows our Adelaide mattress store's quietest day is Wednesday and busiest day is Saturday. So how can you use this information to your benefit?
In reality the best day to visit a mattress store is any day that suits your schedule. However you may find you are able to spend more time and build a better relationship with the Sales Assistant or Sales Manager on their quietest days and that is usually mid week. This may allow you to spend more time to choose the best mattress for you and negotiate the best price.
However if you know what you want already, perhaps you have tried out beforehand. Any day is a good day to great price at Save A Lot Beds, especially if you want a package deal.