[TowerTalk] RG-6 quality ?

[Dan Zimmerman N3OX]

What can I expect as far as variation in cable quality at UHF if I buy
RG-6 at Home Depot or Lowes or Circuit City?

I need a 35-40' run of something with less loss than RG-58 by Saturday
to play around with a new antenna I built in the UHF contest, and it
seems like RG-6 could be sufficient (about 1.5dB loss in 35 feet
according to VK1OD's line calculator).

I wonder if those who have more experience using it know if something
like 4.3dB/100ft is the best case for a good RG-6, or more like the
"normal" loss for commodity RG-6, and if it's the former, do you have
any ideas for local sources for *good* cable?

Thanks and 73,
Dan