You can see that Boswell isn't going full speed because he's a sparring partner, not an opponent. That being said, you can also see that: 1. Boswell crosses his feet when he backs up. How could be get to that level and not correct such an amateur flaw in his game? WTF? Seriously. 2. Povetkin looks much sharper and has MUCH better technical ability.
If Povetkin has a good prep he should be a big favorite. However, having Atlas as a coach must be very exhausting mentally and physically, so on that note I can't discount Boswell's chances completely.
For his first defense an easy fight is fairly acceptable but after this he should defend his title against the likes of Fury and Helenius to gain respect. If he chooses a Holyfield or Rahman after this fight then Ill be very disappointed. Good look to Boswell though as the underdog.
I haven't seen Boswell since his fight with McCline which was long ago so that I have no idea about his current condition. He is younger than Holyfield but not that much. I do not expect anything spectacular. Povetkin should go out of Wladimir KlitschKO's shadow and fight him at some point. Wladimir is not retiring any time soon so it does not make sense to wait that long. Poevtkin has been wasting his prime years. There are good fights for Povetkin even outside of KlitschKOs.