Nauticam is absolutely right, there is no clear winner. WWL1b is slightly cheaper, but there is still a layer of water between the flat port and WWL. There can be bubbles here that the autofocus can focus on. If it is very cold, there may also be ice crystals. The WACP-C tends to be slightly better in terms of image quality, there can be neither bubbles nor crystals, but it is more expensive.
Interceptor had problems with his port, and he generalized these problems to the WACP-C - which is not true. This does not do justice to the quality.