Does security token only polymath? I think there are greater project aside from it as a security tokens. Also the platform tokens are growing eth, neo, ada and many more these are conprises the same content that has rising today.
There are few others security tokens (securitize, swarm, harbor, etc.) but I haven't studied them fully yet so not sure how they compete with Polymath. I'll update my main thread in 15-20 days with few more worth inclusions. Also I'm looking into the real world projects and solutions using blockchain technology such as WePower, I'll include that category too.
ETH is still the king as long as platform tokens are considered, NEO too has proven itself (in fact recently nOS has completed there beta of product on NEO and nOS seems pretty good to me), but new platform tokens are coming almost each month now, some of the worthy mentions are HPB, WAVES, IOST, SUB, ChainLink, etc. This category is getting big day by day, and I am thinking of reviewing some of them as per my capacity and put it altogether in a new thread.