It doesn't really take 10 minutes to go up the hill, only if you do the whole loop.
It is well worth walking up because the view up past Glenrowan, and down to Winton is excellent. Lake Mokoan (now Winton Wetlands), is particually fine at the moment as there is a heap of water returned to the wetlands. The view is very nearly 360 degrees, which for a small hill is quite impressive.
When you have finished this walk (and cache), and feel quite refreshed from being out of the car, pop over and grab this small cache.