I've been trying these over the last couple of days and am starting to make some good progress. I had tried them earlier in the year and it was pretty ugly!

I was originally having trouble just making a decent catch of the tama, and hitting my finger in the right place, but have now got that part quite clean. I am finding though that the ken is getting quite wild when trying to land the aeroplane part. I guess this could be down to my release of the ken not being clean.
I did however find that when I swapped to a heavier Kendama that the ken became a bit more controlled. Would anyone else agree that a heavier ken would be preferred for this sort of trick, or just more practice with whichever kendama I happen to be holding?