Some purchasers of the 409 model complained that the shoes run smaller than other New Balance models.  I agree, but was not troubled because I buy shoes a  bit larger than I need and then put insoles in them for added support.  But they are smaller than the size indicated.  I have worn them three or four times without additional insoles and find the support and quality very good.....no complaints.  And they seem sturdily built and should last a long time.  I am happy with them, especially considering the price.  I think they are comparable to the 623 model, but it is too early to be too confident about that judgment.