Worth a try. In my experience core drilling is a slow process but I've not tried holes that small. Quite often helps to have some water cooling the bit. They might be quite difficult to get started, you need a pilot hole to stop them skating.
Yeah will try with an 8mm pilot. I wondered about water, neither the listing or the reviews mention it but probably can't hurt. I think I'll need to drill them on the floor which means getting the brackets plumb and in the right spot will be tricky but they do have a little adjustment.
That's why I used 10mm threaded rod with a grommet between post and rod. You can mount them and then bend the rod to upright (or whatever angle you need).
Worth a try. In my experience core drilling is a slow process but I've not tried holes that small. Quite often helps to have some water cooling the bit. They might be quite difficult to get started, you need a pilot hole to stop them skating.