Your comment about an 8 year employee not being eligible for PERS benefits is incorrect. 

Right away, you get the 6% that is out into an IRA type account. After 5 years, you are fully vested in the pension calculation which is 1.5% x years of service when you hit retirement age. Someone with 8 years won't get nearly as much as someone with 30 years, everything else being equal. But 5 years is the vesting time for the pension.