I love Vivid and am a huge fan of Lawrence Dickie. Brilliant and it was a few interviews with him that gave me the confidence to launch my speaker line using composite cabinets.
The integration of driver and the fiberglass cabinets that they use are extraordinary. It is always a matter of taste and they tend to not offer deep bass so need to be augmented with subwoofers, but the frequency response they do offer is absolutely brilliant and truly one of the elite speaker companies in the world.
When looking at Vivid (fiberglass cabinets), there are a small number of products that actually compete with them. Wilson Benesch Geometry (carbon fiber), Kef Blades and above (fiberglass), Wilson (cast phenolic resin), Marten (cf or fiberglass in certain products), Rockport (unspecified composite), YG and Magic (aluminum), Verdant (My Company - fiberglass and cf in certain products), Kaiser (rubber composite). There are a couple others but not many others that are produce cabinets that are not mdf/wood.
These non-traditional cabinets offer superior damping and are really special but are pricey.