I actually think that Modcloth provided excellent service. You can contact them and ask them for advice, even like "what shoes would go with this dress," or "what dress would be good for my upcoming date," and they will provide you with a custom list of options for you and they are really nice about it. Also I ordered a bag from this site. A week after I got it, one of the rings that attached the strap to the body of the bag broke. I contacted customer support and they were going to let me exchange it, but they realized the item had gone out of stock. Instead they gave me a generous refund, and I ended up getting my bag fixed at a local store.
The website is really nice. I especially like the search feature, because you can type in things like "yellow dress" and it would narrow it down accordingly, which is not something you find on most clothing websites. The website also has a VERY large selection of merchandise and your pretty much guaranteed to find something you like, though it may be a little bit overpriced. I particularly like the apartment section, they have a lot of cute and quirky stuff. Also did I mention the clever names. Whoever comes up with the names should get an award.
I think it would be awesome if Modcloth came out with real stores. (hint hint)