This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
Whizlabs has a good reputation. The other site you mentioned tries to sell you copyrighted material that was illegally copied (you could call them pirates, criminals). So, of these two, definitely choose Whizlabs.