First, in Australia flip flops are called thongs. The Archies Arch Support Thongs are proving very popular in Australia and are selling well. The are often recommended by podiatrists.
Are they any good for bunions? Of course they are. Anything that is open that gets pressure off a bunion is going to be helpful. The thongs or flip flops have an arch support built into them that is about the same size as a lot of over-the-counter foot supports, so you get the advantage of using a foot support and not having to wear the restricted footwear. That is a good thing. The come in a lot of different colours and are suitable where this type of footwear is part of the lifestyle.
You can buy them here.