I watched both the debates as well. I thought the Channel 4 one was more controlled, Krishnan Guru Murphy is better at managing the candidates to an extent, but I felt he spent way too much time interrupting them in order to pass on journo zingers that at one point got so personal (to Sajid Javid, of all the candidates) that others spoke out to defend him and say he's a great guy. I felt the tone of the debate was too aggressive and negative towards the candidates, and it meant it was difficult for them to really say much when they were being interrupted by the host all the time.
The BBC debate was about as bad, but for different reasons. Emily Maitlis is a decent enough broadcaster, but for whatever reason (I feel the format had something to do with it) debate was second to pointless bickering. Rory Stewart came off badly because he seemed to lack a sense of poise about being challenged on his views that I can only imagine comes from relative inexperience. When Boris did speak he seemed to compromise his position on key elements of his policy statements, especially the issue of Brexit. For the record I think Michael Gove is completely reasonable to say that if a deal is days away from being struck then it makes no sense to leave on the 31st October, but Boris doesn't have the courage of his convictions to insist on what he says is his attitude. Jeremy Hunt managed to make himself seem even more in cloud cuckoo land than he already does by saying the two aims of Conservatives are to cut taxes and increase public spending, without really acknowledging these are contradictory. Sajid Javid has struggled to get out of the starting blocks and hasn't made a real impression.
I felt the BBC debate format was poorly chosen, having no real studio audience meant that candidates weren't encouraged to address their responses to a member of the public which kept them in check during the C4 debate. The people they chose were strange, asking a 15 year old to question on climate change when they can't vote and frankly won't support the conservatives at that age anyway, it's no surprise the result is that the questioner is unhappy with the answers they get.
On another note, I think it's worth pointing out that Rory Stewart brought up an interesting point about prorogation; Tony Blair tried to do this on Iraq and ended up thwarted because the MPs just went and met elsewhere. Proroguing parliament won't stop it meeting, it'll just close the place where they meet.
Edit: Following the third vote, Rory Stewart has been eliminated. He actually lost votes compared to the second vote, while Boris has nearly half the overall parliamentary party backing him.