When you say custom, do you mean kitless? The reason I ask is that kitless/custom pens are generally lighter than a kit pen. So you really don't notice the weight difference near as much as with a kit pen. And this is just a generality. Some custom pen can and probably do weigh more than a kit pen, but the kitless pens I've made so far are much lighter. I've only made one postable kitless pen, and the cap is very light, so it doesn't seem top heavy when writing with it. I am getting ready to redo the cap, and what I have in mind might make it a bit heavier, but I doubt it will weigh anywhere near as much as a similar sized cap from a kit pen.
