If you could install an artificial device to repress instinct/impulse, would you?

I'm asking this to help with character development in a story I'd like to write. As for the particulars on the device, it does not necessarily turn you into an emotionless machine (in-fact, some characters will choose to keep painful emotions, merely to have amusement in their lives) , rather it would counteract any impulse or instinctual behavior that the user (or installer) found undesirable; and bear in mind, it wouldn't necessarily serve as an escape for pain (though this would also be a function, if wanted); but, for example, could free you from the usual patterns of a picking a mate - instincts and subconscious responses telling you to pick a mate based on how likely your genes were to survive with this mate could be suppressed - why you choose what you choose would be completely up to you. I'd like you to be as in-depth as possible, why would you/would you not? What would you be afraid of? Why did you make the decision you did? Any feelings you have on the idea are apperciated.