WU vs KH/s ?

[MrBilling]

I have read that a good WU to hash rate (KH/s or MH/s) is WU being 92% or better of the hash rate.
Is this correct?

On my two BAMT rigs my ratio is about 88%.  After 4 days of non stop running my avg hash rate for four 7950's is 2549 KH/s and my WU is 2249.


On my Windows 8 rig with three 7950's my avg hash rate is 1828 KH/s and my WU is 1662.  Which is about 93%


Does this sound right?  Whats would be the best thing(s) to tweak to get the WU up more?

[Kinetic915]

thats about what I get and I have been told that is good!

[kodo]

I like it thanks