I know that SigNoz uses Clickhouse and focuses more on observability UX.
Quickwit is its own data engine.
Quickwit is its own data engine.
We also have traces, metrics and logs in a single application which makes correlation across them much easier. From what I can understand from Quickwit website, they use Grafana and Jaeger for UI.
Here's our github repo if you want to check it out. https://github.com/signoz/signoz