And last but not least...I personally don't appreciate roleplaying groups where players kill each others' characters over relatively small slights. I believe in some leeway towards each other, especially since most of us put a lot of effort into our characters and prefer them to actually live through an entire campaign. In addition, player killing almost irrevocably leads to resentment.
In general, I agree with this. However, I feel there's a certain exception: Psykers are without question among the strongest characters in the setting, becoming ever stronger with every new sourcebook and every new power published (one game session, we went through an underground complex with massive amounts of traps. That was after the Radical's Handbook and its awesome Sense Mechanism power was published. Guess how many wounds we took after my diviner got fed up with the booby traps and decided that he'd use powers). There are two balances to this power: The fact that at any moment, things can Go Horribly Wrong and that most people assume that things you do will Go Horribly Wrong.
Like others have said though, it could be a good idea to clear this with the other players in a group before making a psyker. If they're hell-bent on killing off any psyker that displays perils, well, there's a pretty huge risk in playing one since there's a decent chance it will happen sooner or later. I like playing doomed characters, but not ones that are doomed at the chance of a dice roll.
IMO, psykers aren't doomed at the chance of a dice roll, but doomed from the point they choose the psyker career and choose to manifest powers when they don't have Fate Points left to reroll nines.
@Illithidelderbrain
Also, for every 10 Corruption points your rare little snowflake inflicts on the party members, they have a chance to get themselves a nice little mutation, and once you get one, getting more becomes even easier.
Forget Corrupting the cell, think of the bystanders - the Corruption rules explicitly state that PCs and other significant characters are the only ones that get the benefit of the 100 point Corruption scale. Everyone else exposed to any amount of Corruption may at the drop of a hat mutate or become insane outright.