It's hugely expensive. For me and my spouse it's about $1,100 a month and that's with Kaiser. On top of it is the $3,500 deductible, $4,500 OOP for individual and 9K OOP for both.
Basically it's only good if something catastrophic happens. You pay through the nose and end up getting medical bills in the mail constantly if you use it.
I would say if you qualify for ACA or other subsidized care go for it. We do not so we are stuck till Medicare.
They only contribute 50% after 30 years or so, if you have less than that their contribution is a lot less. So very expensive to say the least and honestly Alllstate's medical is some of the worst I've seen for a major employer. Not even competitive.