Onlineshoes.com

Full review
Delivery speed:       amazingly fast
Order accuracy:       all my orders (7 or 8 so far) have been accurate
Customer service:    I've called twice.  My calls were answered fast; each time the operator spoke perfect English and answered my questions fully
Overall satisfaction: I have been completely satisfied with my shopping experiences here
Disclaimer:             I have no relationship with onlineshoes.com except as a customer

Longer story:  I think I found this website as the result of a web search.  I was astonished when my first order arrived within four or five days. 

Their website is one of the best I've found for location the product you want quickly.  It has excellent search tools so that you can quickly find the style, brand, color, and size you want. They have a huge selection of brands and sizes. The site keeps track of the shoes you've recently looked at so you can find them again easily; very nice for comparison shopping.  They also have multiple views of each shoe -- top, bottom side, back. This has kept me from making a couple of purchases when I realized that the shoe was not attractive from all angles! 
 
Shipping is free.  You have full year in which to return or exchange a purchase, and if you do, you only pay for return shipping ($6, I think) if you want a refund.  They make returns very easy by letting you print a return shipping authorization right on your computer.  You just box up the shoes (they have to be in the original box, so I guess that could be a problem if you didn't realize that) and take them to UPS.
 
I have called their customer service line for help a couple of times, and a real person (who speaks English) answers and gets you your answer fast. 

All in all, I can't think of any improvements that I would want to see on the website or with the service from this vendor.