Hi Guys,
I do have some of these 'Head Spot' Robos here, but they have only recently arrived and i havent had time to really 'examine' them yet or take any photos of them. Hopefully i will get round to it soon.
There is a big difference between the shades of Agouti Robos already - some are quite pale (especially if they carry other genes) and some are very dark, so i would guess that the same difference in shades of colour would be present in these head spots / marks, so this is probably what you are noticeing.
Also, there is a very big diffference between the colour of very young robos, adolescent robos and mature robos - they continue to get darker as they get older and also look to change colour when they moult too. So this may be another reason why the head spots / marks are different shades.
Like i said, i dont have any experience with this new colour, but hopefully i will soon
Hope this helps.
Tammy x