B&K preamp question

I would like to hear from those that may have experiences with the b&k PT 3 and PT 5 tuner preamps.  I know the PT 5 has balanced inputs which i do not care about but it also sold for $250 to $300 more then the PT 3  when new yet they appear to be the same thing except for the balanced inputs. Is there a sonic difference between these two? Are the insides different parts wise?  Thanks
I have owned two PT3 MkII's and they are wonderful "budget" pieces.  Versatile, well built, very adequate tuner, and a sweet velvety warmish signature.  I can't say for sure of the differences between the 3 and the 5 except for the balanced outputs not inputs

I have 2 of the PT-3 MkII's and they are a steal of a preamp.  I too can't say if the PT-5 has anything other than Balanced outputs over the PT-3.
Am I any better off with a NAD C160/ 162 or mid 90s Yamaha CX2?  I swear I should just stick with integrateds.
Both NADs are fine older budget preamps.  

I love integrateds by the way.