Icomoon is definitely awesome and useful. endtwist and I were craving more of a Compass spriting style workflow for icons, however, which is how this project got started.
First "Action, Another Action..." menu with icons is broken on hover, for me. Blue bg only covers half of it, rest of text is obviously unreadable. Looks like this is the result of the width: 1.25em; in the CSS. If I remove that, then the blue bg on hover doesn't span the box any more. Looks like these icons should really be applied as ::before or ::after, instead of modifying the element itself, as this seems to horribly break things.
For some reason the icons appear to be broken (appearing as the kind of squares you see when a character isn't supported) for me on this work computer using the latest stable Chrome (23, running on Windows 7 x64). They show up right in Firefox, though. Seeing as every other icon font website is working fine in Chrome here, it seems like something is amiss.
We've tested across every major browser with no problems, but it could easily be an problem with Windows and fonts. Would you mind submitting it as an issue? https://github.com/endtwist/fontcustom/issues
Font Custom's intended sweet spot lies somewhere between using a pre-bundled icon font and firing up a fully-fledged glyph editor. For the simplicity of using regular vectors, I think the lack of perfect pixel hinting could be a worthwhile tradeoff.
Unfortunately, I demand icon font being sharp at particular font size. Ideally, you could provide a set of eps/svg files with pixel grids and UPM (units per eM) generator setting for the desired font sizes (eg 16px, 20px, 24px). Is it possible?