Excel for Mac has gotten a lot better - but I'm not surprised if it is still its own thing - with edge cases in format, macros, visual basic, linking to databases and data sources etc. I imagine excel under wine is better than the port to Mac in some respects.

The edge cases are where it can break, but they're getting smaller and smaller as Excel slowly turns into a web-based app.

If you can even get Excel working under Wine. Older ones work fine, but AFAIK there's no way to get the modern Excel working on Wine.