I have been a huge fan of Merrells for years, and bought my first pair of the Merrell Sirens about three months ago, maybe four.  These are the most comfortable of all of the Merrells that I have, and strangely enough, repel dirt like no other shoe; saying that might sound strange in a review, but it's true. Having good cushioning is important to me, because of my arthritis, and these work very well for that.  I do NOT have any pain in knees and back after a long day, and wear them right up until I go to bed.

If you have been hesitant about getting these, don't be.  Whether they are on sale or full price, they are worth EVERY penny.