Aside tha fact that Bunuel could redeem his amount of kudos (really huge but deserved of course) for all gmatclub users
I think question pack is underutilized because :
- first of all is cheap and have a bunch of questions. Official questions. and official questions are official questions.
- gmatclub test is harder than gmatprep and Qpack, so is worth to do it AFTER you have consumed these resources. (As Bunuel suggested during the last chat).
This is the only reason I'm inclined in the first instance for question pack. That's it
KUDOS is the good manner to help the entire community.