Tankini swimsuits are not good for serious swimmers. They are not good because they create an unnecessary amount of resistance. The extra resistance impedes a swimmers ability to maintain the proper speed to "swim seriously".
No tankini swimsuits are not good for serious swimmers. Although it might look good, serious swimmers are burdened by flaps, folds and different materials being stitched together.
i feel that tankini swimsuits are good for serious female swimmers as the cling to the body and help the body stay in a slimline shape also the dont hang down anywhere so water does not slow you down catching on it.