The costume is a nice costume, but definitely not 5 stars. It does NOT come with a hoop skirt as described in other reviews. Additionally, the hat is different - has an orange jewel instead of a buckle (not a big deal, but FYI) - and the jewel (sewn on front of hat) is sewn "under" the curved top of the hat - not to the side as shown in the photo. Therefore, when the hat is worn, the tip of the hat points straight forward, not to the side as pictured.
My daughter is 5 years old - about 45" tall and about 45 lbs. She currently wears size 5 or 6 clothes (depending on manufacturer's fit). The 4/6 costume fit her nicely. Length was perfect - and she's fairly tall for her age. Sleeves a bit short, but decorative 'flowy' cuffs are very long and make up for any shortness. That being said, we live in a very cold climate and I probably need more room to layer warm clothes underneath for trick-or-treating, so I also ordered an 8/10. Honestly, except for the length, there isn't much difference between the fit of the 4/6 and 8/10 - the fabric is stretchy and the waist is elastic, so it looks good. Even the shoulder seams on both costumes are about the same width..maybe 1/2 or 1" difference? Perhaps 8/10 is a bit baggy, but not oddly so. Additionally the hat that comes with the 8/10 is larger than the hat that comes with the 4/6 (as it should be) and is a better fit for my daughter. Being a larger hat, it also has a larger brim. But buyer beware - neither hat has nearly as large of brim as the hat that's pictured in the photo. I think the large hat in picture is really cute and adds a lot to costume, so I was disappointed in the smaller hat that actually arrived. I'm pretty picky but I'm keeping the 8/10. Even the 8/10 sleeves are still a little short on my daughter! But more room for warm layers, and that's key in our climate. If we lived someplace warmer, or if this were just bring used for an indoor Halloween party/dress up, I would for sure get the 4/6. I will just have to get it hemmed. No biggie. It's probably 6-9" too long so definitely needs to be hemmed.
Also, just as an FYI, the 4/6 arrived damaged - 3-4" tear along the seam in the middle of the back of the skirt. A tear that is beyond my meager sewing skills to repair, as the fabric ripped, not just the seam. greatofferstock.com was good about letting me return for a refund.
The quality of the fabric is decent. Better than the cheap costumes you can get at a party store, but nothing overly fantastic. Stretchy, so can fit a variety of sizes/shapes of kids. I would say the costume probably would not stand up to a washing in a washing machine. I'm guessing, based upon the dates of the previous reviews and their raving about the fabric and the hoop skirt, the quality of this costume has been scaled back since. Its still a decent costume, but I've seen much nicer. I guess it just depends on how much you want to spend. The most important point is my daughter loves it and is begging me to wear it everyday - so you cant go wrong with this price.