Do you think that it is good alternative of the centralized ones?

I checked some of them and I think that one of the biggest problems is the liquidity and user experience, but they also have a lot of advantages:

Extremely secure
Users have full control over their funds
Everything you need is public/privatekey, metamask or hardware wallet
It is not required any personal data
No one can stop the smart contract - it is unstoppable, because is running on the blockchain
The code is open source

I have some friends which are building a DEX and they are focused on the security, transparency and UI.
You could check their platform here: https://weidex.market/exchange