Mt TB is due for its 90 000km service - last under current service plan!!

Two questions:

1.Is it worth extending the service plan - it seems quite expensive??

2. Where in Pretoria is best to take it to?? I purchased the vehicle from Westvaal Jacaranda and the sales services was good, but not sure about workshops and their reliability & quality of workmanship?? Any advice based on recent personal experience??