Even if a character with sensitive system doesn't plan on taking cyberware, they also aren't planning on being caught in an explosion. The Shadows are a dangerous place, a lot of cyberlimbs aren't upgrades, but replacements. So I wouldn't call it cheese, in fact its highly dangerous for Awakened/Emerged characters to take sensitive system. For example, if they get a leg blown off, that's one point of essence gone right there, and if they decide to get a cyberlimb replacement, that's another point right there.