I'm doing this particular set of openers on a social networking site (not Plentyoffattiesandstuckupbitches) nor am I doing this on OkCupid and no not Facebook.

I sent out twenty messages per opener, I will post the results below after one hour.

Opener #1:
Message 1: You should really remove your profile picture.

Message 2: Haha, just kidding. I just wanted to say hi

Total Responses To Opener: 12
Total Responses To Second Message: 7

Good: 1
Bad: 6

"you should get a fucking life and kiss my ass"
"bye"
"okaii,, hi"
"okay then..."
"-_- see when you insult me like that, and my son, I won't speak to you.

Jerk." (lol wtf?)
"rightt lol"
"lol hi"

Opener #2:
Based on my profile picture, make one assumption about me.

Don't be boring!

Total Responses To Opener: 3

Good: 1
Bad: 2

"umm a loser"
"uhm..."
"Ah, finally a interesting message XD.
Um, from looking at your picture I am going to assume that you are...a bit of a messy person lol.
Now your turn. "

Opener #3:
I once bare knuckle boxed a grizzly bear... and won!

Can you top that?

Total Responses To Opener: 6

Fun: 2
Non-Fun: 4

"I got attacked by T-Rex then I bit it's fucking head off bitch!"
"i have a vagina , so i always win"
"nope"
"Yeah well I raped a lion in the ass! Can you top that?"
"My Boyfriend has a Huge penis."
"I made it through boot camp"

I think the way you word opener #1 has a more negative connotation to it. For example.

"You should really remove your profile picture"

vs.

"Hey, you might want to remove your profile picture"

The first one sounds like you're saying it because she looks ugly in it. The second one is more of a suggestion and doesn't sound as hostile, and I think naturally she'll want to find out why more versus the way you worded it.

Just my .02 cents.