Hello there!
I just got my third bengal here, more than a year younger than the other two (she's 3 months old and the others 19 and 16 months). I was a bit anxious about how she would fit in, but it's been a week now, and everything is fantastic!!
There was hissing and growling when they first met, but now they play and eat and almost sleep together. I think we'll pass this last step over the week-end!
I still don't let her alone with the 2 others when I'm not there, she's still too small and I don't want to take any chance until she had explored every corners and knows her limits. But so far it's been a very positive experience!!!
I don't know about males and females mix, cause I have only females
. But as bundles said, it depends a lot on the cat's personality!
Hope it helps a little!
Bye,
Sysh