About Blockstream latency I could say this: their Greenlight servers (where your LN node reside) became quite used by many users and they didn't upgrade the infrastructure.
My advice (even that I know you will ignore it) is this: use multipke LN wallets for each situation to be prepared. And read my guides.
You are comparing apples with oranges.
Blockstream is self custodial node.
Coinos is a custodial service account (just an entry in a database).
I am not taking any sides, just commenting your wrong perspective between custodial or not.
Please read this comparison guide
https://darth-coin.github.io/wallets/lightning-wallets-comparison-en.html
About Blockstream latency I could say this: their Greenlight servers (where your LN node reside) became quite used by many users and they didn't upgrade the infrastructure.
My advice (even that I know you will ignore it) is this: use multipke LN wallets for each situation to be prepared. And read my guides.