Well, this is my beta reader results. It's been not bad, I'd say.
I asked in the two writing groups I was involved in. In one I received nothing, no offers. But this isn't a fair assessment because one of the writers there is my usual beta reader and read an early draft version of my book before I reworked it.
In the other one, I received 1 offer. Nice.
Crit Partner Match
I have had 0 offers so far from Crit Partner Match.
I asked at Superhero Nation. I received 1 offer. Nice.
I didn't ask. They're not big readers.
I received a request for a sample.
So, 2 and 1/2. Well, 2 chapters. Not bad, not brilliant. I'm waiting on them coming back, and then I'll find out if my betas are any good.
In the end, I think the best way to get beta readers is to have a blog or twitter or join a forum. Make connections. Make friends.
And ask your friends.
But friendship is a 2 way street, so be ready when they ask you, too.