Can I put 215/50R17 or 225/45R17 tires on the front wheels of a 1998 Boxster

Hi,

We recently purchased a 1998 Boxster which came with pretty poor tires on it.  I am looking to replace all 4 in the near future.  However, I am not finding quite what I want in the OEM size for the 17" wheels.  OEM size for this vehicle is 205/50R17 in front and 255/40R17 in the rear.  While there are a number of decent tires for this fitment, what I am currently looking at is the Bridgestone Potenza RE-71R.  It has the correct fitment for the rear wheels but not for the fronts.  The alternatives in that tire are either a 205/45R17 (too small) a 215/45R17 (slightly small) or a 225/45R17 (very slightly small).  The closest in diamter and circumferences would be the 225/45R17 which is off by 0.4% in circumference while the 215/45R17 is off by a little less than 2%.  Researching wheel size specifications indicate that the 215/45R17 is optimal while the 225/45R17 will fit but be at the limits for the wheel width.  The question is, has anyone tried this with either of these tire sizes and, specifically, will the 225/45 fit and if not would the 215/45 be okay as an alternative.  Finally, what concerns would I have with changes in handling?

Thanks!