I may put a lot of money into my road bike but don't spend money just to spend it. the zipp stem is one example, i see no reason to spend four times as much for another stem. the zipp rides excellent, is very stiff, and really inexpensive. spend money on your bars.
If you are looking for a great bang for your buck stem, this is it. Not only is this stem stiff it is also fairly light. Matches up well with all the ZIpp service course bits. Comes in all lengths in the 6 degree.