Most of my investments in cryptocurrency are Ethereum. It is this cryptocurrency for me that is one of the most valuable. During a massive drop in prices in the cryptocurrency market, I sell Ethereum for USDT when it falls and buy again when the market starts to recover, when the price starts to rise again. I had to use this tactic in 2018 and 2019, while I made good money. But I also use USDT as a storage for my money in cryptocurrency equivalent, and only if necessary convert them into fiat funds.
In addition, I use MyEtherWallet to store USDT and Trust Walet as a wallet for expenses, which is very convenient for me.