I've used WDW Florist, Peggy's Sweets and More, and Gifts of a Lifetime. They were all very good to work with. WDW Florist did work with me to come up with something very personalized, however it ended up being very pricey. Jane at GoaL was terrific also...I had an issue with a non-delivery and she sorted through it right away..it was the resort's fault (Dolphin) not hers, but she took care of it. She did allow for some personalization but not as much as I would have liked, and it was pricey also, but not as bad as Disney Florist. Which brings me to Peggy's. The reason I had to go with the other two was that Peg was busy doing family stuff and had to forgo doing boxes for the rest of us. Man, you gotta prioritize Peg...the needs of your dd or the needs of the many looking for magical touches while in WDW!!!! Just kidding!!! But, Peg has done several boxes for me and they have been wonderful. One thing I like is that she uses a box rather than a basket...I can just fold up the box and lie it flat in my suitcase, or just chuck it at the end of our stay. I have been able to personalize exactly how I want. Even if something isn't listed on her site, if you let her know what you are trying to accomplish, she'll offer suggestions and go out and get it done. I'm really looking forward to using her again in Oct for my dd's 13th b-day in WDW...just have to figure out what I'm going to put in the box.
You can't go wrong with any of them, but I have to really recommend Peggy's Sweets and More as the number 1 in the group.