I enjoy my flip flops and have been using Crocs brand for a few years now and certain ones (not all) of theirs are fantastic but....the treads tend to wear down on the bottom and then it's like walking on black ice or something when the surface is wet.
The shoe itself is still in great condition with plenty of sole thickness, so I just take my angle grinder and cut in some new treads. Really gives me much more usage from a pair!