We used Display My Art this year and they were fantastic. One of the things that I liked best about them (aside from great service) was the fact that each child can log on to the website with a code that is printed on a free fridge magnet of the child's work and see what each item will look like with your child's artwork on it.
The only recommendation that I do have with art fundraisers is to get the art teachers on board with plenty of time in advance. That way they can write it into their curriculum.
We definitely plan to use Display My Art again.
We've used Original Works in the past, but found it difficult to get all the volunteers we needed to help the kids create the artwork, etc...This year we've been using ARTSONIA. It's supereasy...We photograph or scan artwork from both the art classes and regular classes and upload it. At this point we have over 2400 pieces on the site. Family and friends can become fans and see the "galleries" of the kids' artwork. Then they can comment.
There's also a giftshop -- I've been pleased with how quickly items arrive and the quality.
The drawback is that we only receive 15% of the items sold, so it ends up being a lot of work for little money, so we consider it more of a community thing than a fundraiser.
Square 1 printed the wrong price for an item on the order form, they were alerted to the error and ok with it. When the bill came it reflected the higher price and making us responsible for the increased amount. It comes down to customer service, which was awful. In the end the ate the cost, but shouldn't have made us argue this.
I am interested in hearing about the bad experience with Square 1 Art - my daughter's previous school worked with them and it went smoothly. We are planning to use Square 1 for our spring fundraiser (this is at a different school).