In episode 327 of Semantic Mastery's weekly Hump Day Hangouts, one participant asked if GSA Links are also Web 2.0 contextual links.
The exact question was:
2) Are GSA links also Web 2.0 contextual links? 2.1) Why do you recommend to buy 1st&2nd tier web 2 contextual links and in the 3rd & 4th tier to buy GSA links?
