I'm planning to post tournament NEM for all teams later this week.

As always, all raw efficiency data is from the sublime kenpom.com. I used the ratings through all first round games to make the comparisons. (For my Sweet 16 reviews, I'll update the ratings through the end of the second round, and so on.)

Best games (by combined total NEM)

 ResultTotal NEM 
1.Duke68Cal53 61.4This one had the biggest NEM gap (51.5 to 9.9) of these top 5.
2.Kansas St.84BYU72 54.9
3.Northern Iowa69Kansas67 54.4Obviously, one of the biggest tournament upsets.
4.West Virginia68Missouri59 50.4Like Kansas State, the Mountaineers are another 2 seed playing well and not getting a lot of notice.
5.Ohio St.75Georgia Tech66 50.0

Top overall performances

1.KentuckyWake Forest60.8No surprise here. The young Wildcats may have finally grown into the role of tournament favorites.
3.DukeCal51.5When you turn over the ball on only 8.6% of your possessions, you're going to win a lot of games.
5.Kansas St.BYU44.1The Wildcats are playinkg very well (average 37.5 NEM in two games) but not getting a lot of attention. If they win two more, that will change.

Top offensive performances

1.CornellWisconsin56.3With CtD's alma mater out of the tournament, the Big Red may be the sentimental favorite. How can you not enjoy their press conference shenanigans?
2.KentuckyWake Forest42.3
3.BaylorOld Dominion31.2Quite a difference from their round 1 performance.
5.Kansas St.BYU27.4

Top defensive performances (lower scores are better)

1.DukeCal-30.0Duke shut down the third best offensive team in the country, holding the bears to 42.7 eFG%.
2.PurdueTexas A&M-27.2The offensive struggles without Robbie Hummel continue, but the Boilers shut down A&M enough to escape in OT.
3.WashingtonNew Mexico-22.1
4.Texas A&MPurdue-21.1
5.Ohio St.Georgia Tech-20.4Tech has been careless with the ball all year long, but turning the ball over on 28.5% of your possessions and shooting 44.8 eFG% will send you home.

Worst overall performances

1.Wake ForestKentucky-15.8The Deacs couldn't stop Kentucky (16.3 defensive NEM) or score against them (0.5 NEM).
3.New MexicoWashington-4.8
5.OhioTennessee-1.8The Bobcats couldn't keep the magic going in the second round.