It will all depend entirely on personal needs. Many things can be done, but can take a lot more work. And some things are just not really possible or ideal.
For example, if you ever use more than 1 application at a time (such as writing an email while looking at a web page), or if you want a larger screen, hard drive storage, USB devices, file storage, user accounts, etc.... You may find it inconvenient. Some web pages won't load properly, and the site may have an app, but it might be limited.
Ultimately, a Surface 2 / Pro 2 would be a far more qualified replacement to a traditional computer as it addresses pretty much all of the shortcomings.