I tried the free offer of Blitz Time and attended one session which consisted of a teleseminar on a chosen topic and then the blitz networking (like speed dating).
The experience was interesting and I could see if one was to use the service could provide valuable networking if you are paired with individuals within your niche.
I don't think that at this point in my business development that I would spend the money on membership. I am currently using Social Media, Client Referrals and Business Contacts to build my business.
Hope that helps