Very sluggish slicing at hitpoints

Im having huge problems with Nuendo 8.2.1 becoming unresponsive or extremely sluggish (10 seconds waiting to open mixer window etc) after slicing multitrack drums at hitpoints. Im wondering if it’s just me?

If I take 12 tracks of drums in a folder track with group edit enabled, and add hitpoints to the hi hat track (lots of 16th notes) it detects them just fine. But when I go to the quantization panel to slice at hitpoints, the entire program grinds to a halt. It takes several minutes to do the slicing and come back “to life”. But when it does, everything is extremely laggy. Especially zooming.

Is this function working properly for others? Or am I asking too much of it to slice at 16th notes over 12 tracks of a 3 minute song?

Thanks!
FYI: This is a quad core 3.8G i7 Win 7 rig with 32 gigs of ram. No plugins going on etc… 48khz/24bit