I've been in one of her classes before.
Although she does give us an insight into her personal life, it's all just to make the class more fun - but if it gets out of control she knows where to draw the line.
Some lessons it's all work and there isn't even one opportunity to speak to the person next to you.
Diab likes, no LOVES, to stick to the rubric, something that no-other teacher I've encountered has done - in the sense that we analyse the rubric and learn to pick out how portions of exam question relates to it.
She's had to reduce and combine her classes because of the stress it puts on her (she's pregnant, haha), so I don't think theres any room left in the class as it stands.
I personally think she's one of the best English tutors you could have, but then again, thats just me.
Make your own choice and just be sure you feel comfortable about it.