Both are pegged with usd so both is a good choice for storing either USDC or USDT. The difference between the two is USDT is highest traded stable coin than USDC. USDT is also the most recognized by many crypto enthusiast as the first Stable coin. For me, I would choose USDT and leave it than USDC although both are pegged with USD. There's nothing wrong with USDC but I preferred using the first Stable coin as many people called it the first stable coin. It's your choice.
If you pay attention to the USDT price since the Luna crash, it has not returned to a 1:1 stable price, it should be a question whether USDT is really pegged to a 1:1 dollar with a 100% dollar backup?
Then see the comparison with USDC which remains at $1: 1 USD. I would choose the opposite, USDC is more stable 1:1 nowadays than USDT.
