Started playing in 5th, only played friends so we didn't abuse the system, it was lots of fun with a lot of details like shooting off chariot crew and having it randomly rampage around and so on. Lizards save couldn't be modified below 6+ and skinks had 6+ saves, always cool saving those and making ninja comments. Oldest slann was a power house in combat WS6, S6, T5, W8, A8. But as said lots of balance issues and herohammer.
6th and 7th started great but devolved into skirmish domination and armybook creep.
8th is deathstar heaven and dice rolling exercise but with restrictions it might just turn out great.
The best, I don't know maybe start of 6th.