Need Help Deciding on a New Lens

[slickhare]

So I'm hoping to be the proud owner of my first new lens soon. But I'm having trouble deciding between two Olympus Zuiko lenses.

the 18-180mm f/3.5-6.3: http://tinyurl.com/2ow6lt

and the 14-54mm F2.8-3.5: http://tinyurl.com/2j7hv6

I do art photography, as well as events and portraiture. I can't decide if I want to have more versatility in one lens, but sacrafice a little quality, or go for something higher quality but limited?

 

[slickhare]

Perhaps I need to be mroe specific, the range that I work in varies, be it getting close in doing some still life, or shooting a sports game. I find the higher quality of the 14-54 attractive, but the range to be somewhat limited. The 18-180 may take a hit in quality, but I'd only have to use one lens for all my shooting. So basically I'm trying to decide if I should up the quality of my shots in the short to mid area? or just cover all the bases?