Depends of your definition of "fine". The linux kernel works fine indenting with tabs but it mandates 8-space tabs and a lot of code ends up looking borderline unreadable if you use anything else, meaning that the only thing they get by using tabs is slightly smaller file sizes. Besides if you want to enforce the 80column limit you have to standardize a tab width anyway.

It's simply not worth it IMO. The pros are simply too small and inconsequential to justify not using spaces on new projects. Although now that automatic code formaters are becoming ubiquitous it really doesn't matter what you use in your editor I suppose.