As you say Paul, not your best ever shots but still good.
If I could be so bold as to suggest a way of diffusing your ring flash that I have found works really well. A couple of weeks ago I started on some intricate surgery photography for a client and the only practical way to light the subjects was with ring flash so here is what I did with quite a fair bit of success.
First I cut out two flat pieces of polystyrene from a throw away plate, the same shape and size as the two flash tubes and placed one piece over each of the tubes and secured them with a piece of white surgical tape. Next I cut two lengths of white foam packing material and once again attached one piece on top of the polystyrene and attached it in the same way.
Now the trick to this is
Not To Use the foam packing material that comes with electrical appliances etc as it does not offer enough diffusion when used with a ring flash. It works very well when using a normal speedlight etc as the flash is further away and you can make up a secondary concave diffuser over the lens much like how Kurt does his.
The material to use is the packing material that shower screens come edged in, and because it comes already shaped to go round the edge of glass screens etc it is very easy to attach it to a ring flash. It is also thicker so only one layer is needed and because it is rounded so to speak it offers diffusion in all directions. I obtained some from my local B&Q store. I just went to the kitchen & bathroom section and asked if they had any to spare from their display units and they obliged with quite a bit without charge.
Hope this helps as it has certainly worked very well for me.
George.