Thanks for the info
The only similar plan I found was the special offer of Newsgroupdirect, only launched some times a year (1TB / 50$ too, same kind of service)
So it's a good news from Astraweb ! Juste some people say they don't have a good completion. It's true I've seen in the past some incomplete post which were complete on Newsgroupdirect or Blocknews. But it's hard to make a global comparisons.
A really good point of this plan is also the ability to share the account.
