Situational. From the perspective of the medic, for stats, points, etc, Kritz has plusses. You get more assists, fewer deaths (as long as you are in a team which covers chokepoints, and you watch your back, not rushing in invulnerable, and retreating vulnerable, means you die less). You also can help wipe out the other team for a push. However, it's frustrating watching allies die, being helpless against sentries, and trying to fight ubers.
Meh. I used them about equally pre-update, depending on prevalence of sentries. I'll do the same after the update.