I'm voting for none of the above! If you want to make a few odd trinkets that don't require that much precision but do require some odd live ends, then any of these are ok, but for pens my opinion and experience says they all suck. Because the tips are interchangeable, they tend to have a little slop in them so that you can remove them and put in a different one. All three of those, the shafts on the replacement bits are straight. Therefore you end up with a little bit of slop in your live center..and although it's just a little bit, it adds up real fast when you also have length from center to center to consider. Like a deck that is a quarter inch out of square but 40' long is 40 quarter inches! That's a big deal. I would only use a single purpose 60 degree live center. On my machine I have a live center that can have the points interchanged, but it is not a cheap center, and the interchanging points are tapered so they sit solid..I don't know if they make a set like that for a smaller wood lathe. The tapered points are sold separate too..but I have no need for anything but the one so that's all I have. For pens..just get a $12 live center is my opinion.