I managed to go to Paris to check out the micro and the small phantom. For those interested, here goes:
1. Small phantom is definitely heavier than micro. It is as heavy as mini, in fact. I had the mistaken notion that small phantom is in between micro and mini. Definitely not! It is similar to mini in weight.
2. Small phantom is easier to find. I saw gorgeous colors at Victor Hugo in Paris (navy blue with orange lining, beige with blue lining). Micro has zero inventory in Paris.
3. Ease of use - Phantom too open for my liking. Even more open than my LV neverfull.
4. Looks - depends on the eyes of the beholder. I think phantom is more stylish but can look messy while micro is more neat.
5. Staying power - your guess as good as mine
6. Small Phantom was eur 1700 I think.
I sadly passed up on the small phantom. Way too big for me. Without content, it already felt heavy. I loved the color navy blue with orange piping. But just not practical for my lifestyle.