I like the higher sanitary level, but I admit there are some issues that I haven't worked out with the new packaging yet:
1). harder to de-gas than the vials - I've lost some yeast when I cut into the pack. was much easier to crack the top a few times to release.
2). harder to get all the yeast out - with a vial, I used to pour about half the vial, recap, shake up to get all the yeast clinging to the walls of the vial, or at worst pour back some wort to the vial to help. hard to do with the pouches.