long range high fidelity PCR

[Tim Bullock]

Hi,
   I'm interested in PCRing out 5-8Kb bands from a BAC to make a targeting 
construct for a knockout mouse.  Therefore I need a polymerase that is 
capable of performing long-range amplifications with very high fidelity. 
Yield is less of an issue.  Can anyone recommend (from personal experience) 
anyone of the myriad of products sold by various companies?

Thanks,

Tim