Fantastic news Ian, great feeling that first x country navex isn't it!
I did my first navex a couple of weeks ago, and as you say, its great fun but mind blowing! My brain was fried by the end of mine and I only just managed the "Aviate " part of aviate navigate communicate (and goodness knows what the poor air/ground radio guy at Peterborough Conington thought when I called him up!
You mention circuit bashing, as you have stated navexes I am guessing you have gone solo? I hope that you're enjoying your training as much as I am (despite the wobbly bits
)
Good luck with it all, and if you haven't gone solo yet, tell us all when you have