UPDATE:
After breaking these in over a day or two, they were SOOO comfortable, and I definitely would buy them again. I guess my feet were just accustomed to a different style of flip-flop. I wear these every day now -- I love them!

OLD REVIEW:
I'm accustomed to wearing Skechers Cali flip flops, which are absolutely awesome but hard to find in a style I like these days.. So I tried Rocket Dogs. They seemed a bit tight when I first put them on, but I forced myself to wear them for a day to let my feet get used to them. These are very comfortable when walking, however they are super slippery due to having no traction on the bottom, and the thong part cuts into my toes when sitting down for some reason. The arch support is a nice feature, and I'm hoping with time the rest of the shoe will fit better on my feet.
Bottom line: I'll keep these because they are not completely horrible and the cost/hassle of returning would be more trouble than it's worth, but I wouldn't buy them again.