Generally not great, as Dillo doesn't support Javascript and most modern sites are using it to create content. But if the site degrades well without JS it should render reasonably well.
http_user_agent="Mozilla/5.0 (PSP (PlayStation Portable); 2.00)"
Then a lot of sites will load a compatible version.On Gemini, there's the Lagrange browser, and gemini://gemi.dev with a nice set of services too.