Welcome Adam,
All comes down to what you value and enjoy within the game. Grange has two golf courses ranked in the top 50 in the country (that are polar opposites in design aesthetics) plus a gym and top class facilities. Considering the price they charge I would actually say it is arguably one of the best value for money tier 1 memberships in the country. In comparison to West Lakes; a single 18 hole tier 2 course with congestion issues and a very large membership I would say the price difference is more than justified.
(based of where you live) If your looking for a value for money option I would consider westward ho (Adelaide Shores) as it is quite a reasonable track for the price you pay.