After careful measuring (repeatedly to be sure) I ordered the XL.  I am 5' 7", 154 lbs., and busty, so I ordered to fit my bust, which is 41.5".  I wasn't worried about my waist (33") or my hips (39") with this style, as I also ordered a wide navy stretch belt to wear cinched with the dress, and of course, the bottom flares out so this style works for small, med. or large hips. (I normally wear L/XL in shirts and dresses, and size 8 in jeans)  I received the dress just today, on schedule.  Before trying it on, I first carefully ironed it with a steam iron on the next to hottest setting, as it was very wrinkled (cotton does that) and was expected.  I was much relieved when the dress fit just fine.  I had no problem with the side zipper sticking, or buttons straining across the bodice.  I already had a short crinoline from Grace Karin, which gives the very full circle skirt just the right "lift" without being too full, and creates a very nice look overall, in my opinion.  The length is just right for my preference;  about mid-knee.  Worn with the navy blue heels and belt, I am quite happy with the overall look of it and craftsmanship.  My husband thinks it is a great look, and wants me to order more.  I'll be wearing it to dinner tomorrow evening. (Its a nice classic look without being "costumey", though it could work well for a '50's themed party with the right shoes and accessories.)

My only "complaint" would be the seller does not have the green one in my size anymore.  I would definitely order it if they did!