Yes, thanks. I will need to try one. I've got an Ayrtek but, like you, it doesn't fit very well - the grill sits too high - though it's the best I've found so far. I already know the Senior Masuri won't fit me, so I'm hoping to try a Senior Large when available. 'When available' is proving to be the issue. I appreciate that Masuri have had their problems since repatriating production, and I realise they're bound to concentrate on satisfying demand from statistically 'average' heads, but you'd think they'd knock out a few in the large size.
A stockist once told me that part of the popularity of the original Masuri was that it either fitted you or it didn't; but when it did, if your head was of average size and shape, it fitted really well. So it's interesting what you say about the adjustable back, which suggests that the Vision Series errs on being over-size, with the ability to adjust it to make it smaller. I live in hope.