Quote From TreeofLife:
Actually I mean before you print the final version, so after your viva and then after your corrections have been signed off. If you do it before the viva, you may have a lot of revisions to make and it's easy to introduce new mistakes when you are making your corrections.
That's a good point. But I don't know if I'll have the confidence to submit thesis for examination without it being proof read. Maybe I should budget for both, especially if I get a lot of corrections.