This site did not show evidence of storing passwords in plaintext.
This site does allow secured connections (https)
This site did show a clear way to unsubscribe from their emails
This site does verify your email address.
Below is a sample of the emails you can expect to receive when signed up to DiSC Profile.
Thank you for registering at our site. Please click the link below to complete your registration: https://www.discprofile.com/CMSPages/Dialogs/UserRegistration.aspx?userguid=6f698618-4a60-44ea-ace3-5aa2655065a3&hash=45858e3f0283088cfe910f6d6519c9530bead6cedbdfc6b0e721c441eec08ca8
You can find your credentials below: