I have only worked one neutured male. As Hunter said, he slipped into defense very easy and really could only work in defense.
I have the only females in my schH club and they are intact and all the females in my SDA club are intact so I can't help you there.
As for if it kills drive or not. I don't think there is a way to test that.
Oh and for what it's worth, every dog I have ever had including child hood dogs have died of cancer and they were all altered. So don't let the fear of cancer change your mind. Think long and hard and decide if an intact dog is something you can handle and be responsible for. Good luck!