Tested it a bit on a 2000 LOC python file, autocomplete is sluggish compared to VSCode (VSCode completes almost instantly but Zed waits about half a second before doing so). I didn't configure anything so I'm a bit disappointed...
Zed's ootb Python experience is poor since they use pyright as the LSP. There's threads on the issue tracker about replacing it, maybe check back in six months.