for a week? I don't see a problem, just dont drive fast and crazzy, and make sure that the rears have same tyres and replacement goes to front. You want youre driving wheels to be nice and stable. Think of it as of driving with donut for bit long. I've seen some people do that, and despite all the recommendations not to do it, for city driving its ok (for shot time like you say).
'07 TiAg E86 Z4 Coupe 3.0si