I've checked all the cryptocurrency price monitoring sites and what I see are the most reliable coins that can be relied on are GUSD (Gemini Dollar), DAI, and Paxos Standard (PAX) price changes that are not too big since it first appeared which became a reason, please check it yourself 
Of course, there are a lot of stable coins in the cryptocurrency market, but not all users of cryptocurrencies have the same relationship to all these coins. I believe that all the same, and USDT or trueUSD are the most popular, because this is what the capitalization of these coins says.