My Group is in the Wispering Cairn, and though we played 4 sessions a 5 hours so far, they haven't even seen Alastor. Maybe it's due to the fact that our heroes have a lot of personal business to settle, so they didn't dive in the Dungeon right away. Seems that Diamond Lake (and some of its inhabitants) is far more attractive to my players so far. But that will change soon enough *evilgrin*
I've just finished play of EBK. It took us two 4-hour sessions.
Whispering Cairn took us 3. Three Faces of Evil took us 4.
Have other groups found the adventures took similar durations to complete? Longer? Shorter?
My group finished Blackwall Keep in 1 six hour session. It was freaky, and set us back a few weeks as we had to wait for the next adventure to come out. I ran side stuff but still as most of my group is rather inexperienced I had little to do for "background role playing".