The biggest advantage to some Highmark plans is their portability into other blue cross blue shield providers. It’s not all plans though and maybe full coverage in other regions isn’t a concern for you.

I have had individually purchased plans from both of them going back over a decade. Years ago there was a lot more difference- now their offerings are largely the same due to their direct competition.

Your biggest concern might be maintaining your current doctors and providers. In that case you need to look real close at any plan because both play games with provider networks.