The manga isn't cannon.
I don't think that Virgil has it in him. He won't kill his brother. Evan after all that has happened with him, he won't kill his own brother.
This is my last post on this thread.
Evidence you say? Alright, one sec (Editing)
1st is at the top of Temnigru after thier first battle. He had every chance to kill him, could have done it right there with Yamato if he wanted to. But he didn't. He awakened Dante's powers on purpose.
Think about it. Virgil already had his power, so he must have known how to awaken Dante. Maby he thought that even with this power Dante couldn't stop him, but he wanted Dante to at least survive the opening of hell into the human world.
2nd is the last battle in DMC 3. During the last cut scene when the two fighters run at each other the last time, Dante wasn't the faster one neither did he swing with more skill. Watch the scene again, Virgil outright fails to swing. At the end he could not bring himself to kill Dante.
I also totally agree with your firs post, miss-darkside.