Eh, I don't feel like they accomplished much. Really I think it was a missed opportunity.
I don't think he was actively working with the Russians. The better strategy would have been to hammer him on Comey's firing. Why was he so effusive back in October, then fire him with no paper trail leading up to it? Did he receive complaints on Comey's management of the FBI? When and how often did he and Rosenstein discuss firing Comey? What did Trump have to say about firing Comey? If his endorsement of Rosenstein's memo was his main basis for firing Comey, how does he feel now that Trump has pointed to the Russia investigation (no less than 3 times) as a main reason for firing him? Why was he able to quote the sub-paragraph of DOJ policy for recusal, but didn't know the policy for not answering questions? Did he not review that with DOJ lawyers? Did he not think it would come up?
I know some of these questions were asked, and he didn't answer, but they should have kept asking. Harris was on the right track.
Fake edit: Tom Cotton makes me embarrassed to be an Arkansan. Sorry, everyone.