Post-MBA PE Group

Hello everyone. As someone who isn't as familiar w/ the in's and out's of the MBB world, I was hoping to get some answers that speak to post-MBA life here. If anyone has any direct experience or knows anybody with answers to the following questions below, insight would be much appreciated:

1- What do exit opps into MM PE look like if you've participated in PE group assignments in MBB (specifically how realistic is exiting into PE from MBB? Is getting into PE from here common? Tough unless you have a PE background? Rare?) Or how about for people who specialize in a sector (i.e. Healthcare) - same questions above.

2- I hear Bain is cream of the crop for its PE practice, but what are the next best opportunities for someone who would be looking to get into consulting with a later goal of exiting to join a PE fund? (Is there anything aside from the obvious answer which I'm guessing would be McKinsey's PE practice and BCG's PE practice?)

3- I hear you get staffed depending on (1) where your work experience/expertise lies; and (2) whether you push for something specific. Is this the case? If so, then is it safe to assume that most people in the PE groups at MBB firms are ex-PE professionals, and a small # are people who find PE interesting but may not necessarily have work experience in PE/M&A/IB?

4- (Regarding Bain & Co's PEG rotation), is it possible to be involved in this for longer than 6 months? What if you're a rockstar?

Let's get the ball rolling with this. Thanks everyone, I appreciate your contribution.