Blacksmoth mandrels

In the pile of things that I bought with the Peter Wright anvil, I have two mandrels:
The second mandrel is basically a cone with a 5/16" steel plate welded to it.
Anyway. I use this anvil mostly for straightening stuff out. I am not really a blacksmith, though I do blacksmithing from time to time. (I have a tiny forge)
Out of these two, I want to get rid of one and keep another, for things like repairing smashed ends of tubing or rings etc.
My own thinking is that it would be wiser to keep the second one, as I could just put the flat part into a vise and hold it stead. Whereas the first one is a more specialized tool that I do not need.
Am I way off with this analysis?
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