He was an evil bastard, no argument and I see how foreign-backing made him more resented. But he was not replaced by anything better. I've gotten into a lot of debates with people who claim the revolution was a purely good thing.
As for the Savak comment. True, they would be harsher. But so would the Mullah's men if not for one thing. Technology. 30 years ago they didn't have tweeter, cellphones, instant news-feeds. A slaughter could be pulled off as long as the cities or borders were sealed. I have no doubt the Iranian regime would be doing that if they thought they could escape the world's eye.
I hope this time the Iranians get the democratic government they've been hoping and fighting for.