Thank you very much for your response, it is very helpful. It is such a poor service of Meridian to just stay quiet on the matter. They are expensive subs. I am happy with my DSP7200 but would like to add a sub to be less dependent on room modes and add a tiny bit off 'trouser flapping'. The DSW looks good, can be controlled via IP with my 218, integrates well and is not too big. However, it has no specs ever published, has limited settings and is expensive. I think it is such a missed opportunity that you can' t control the crossover outside 120 and 80Hz. The surface area of the 12" DSW driver is smaller than the 4x8" drivers in the DSP7200, so I doubt there will be much gain.
All considered, I will wait for the new DSW that may come out this year or I will look for analogue options. But then I would be worried about the latency of the DSP making the sound not coherent. The incomprehensible challenges that life serve us.

Main: DSP8000SE< 218 < Farad Super3 TMCB < PS Audio P10. Room correction: Focus Fidelity.
Second: Fostex Fe206NV2 < Audio innovations 500 valve amp < Wiim Pro +
Study: DSP33 < Reviver < MS200
Server: ROCK + Tidal on NUC, fiber on 2x cisco 2960, HD-Plex LPS.
Gone: DSP7200SEu, DSW, DSP5500mkI & DSP5000mkI, 508.20, 210