Hi,
Do not be put off buying a car with SBC braking system, it really is an excellent braking system. Just check the service info to see if there has been a change of pump, and it is possible that a 2005 vehicle may have had a new one in the past. If not, then just be aware that these days you can buy a replacement Bosch pump from Germany for about £600 and get an Independent to fit it for you. It is no longer the £1500-£2000 that it used to be from a main dealer. Also can be a bargaining point on the price of the car?
Steve