First things first, this mode would be nice to add so fights in op aren't as long and you don't have to break their armour for a kill. From what I've seen the only downside would be that you can be one-shotted with an axe or easily killed. This depends on whichever perspective and the chance. In order to get one-shotted by an axe, you need hardcore and normal with half-health which is rare since everyone these days does op. If UHC or normal is chosen, then the person would most likely choose the other health boosts (if they are smart enough). If not, then players need the the axe that does the most damage. After that, they need to crit you with the axe. It seems like a rare chance for me since hardcore is looked down upon. If voters are sane, they will probably choose a good health option for the respective mode. This is a perfect way for some players that hate op to like op.