We haven't seen this issue. What environment (VS2008, VS2010, 32bit/64bit, Linux) are you using. How long of a lag are you seeing?
How big is your file geodatabase? Have you seen the same behavior with the samples?
Using a fresh install of the VS2008 version of the API I don't see any slowdown in any of the samples. I'm using a Windows 7.
I just unzipped the .zip file on a clean machine. Are you using the 32bit or 64bit version of Windows 7? Are you using a local drive or a network drive?