Lip/Groove feature...baby or bogus!?

Hey folks,

SW2010 SP2.1.

Wondow7 x64 and all the proper and approved hardware...

I have a user that is using the lip/groove tool, works ok sometimes if the surfaces are typically planar.  The issue is the amount of time it is using on rebuilds, on a very small part (8"x4"x3" overall and only 40% of the edge is being used to generate the lip groove), one of the lip/Groove features takes over 25% of model time, 235+ seconds, and another lip/groove on the same part takes up 122+seconds.  Seems like this tool is having problems determing what it's intended job is.

Anyone else seen crazy times like this?  Is this because it is a relative baby or just a junk good idea feature?

I want my IDEAS software!!! 

TIA

SolidworksParts And Features