6 life is a BIG BIG deal in VLLD since u have like under 60 stats to play with (including stats quests)
well its this but its more that 8 min damage>>> 7 max damage
because some people do min-only jewels and what happens is lets say your Axe does 7-10 base damage, now with 8 min it goes to 15-16 as it couldnt have lower max than min
giving 15.5 average damage up from 8. whatever
wheras 8 max damage would do 7-18 which is like.. 12.5 average
so thats why that jewel is a lot better. but yes 6 life is also nice