In the case of binoculars you can change that to "pretty much always." I hunt with an old '60's pair of Bausch & Lomb 7X35 Zephyrs that I bought on Ebay for $135. To me they look almost as clear as my friends $500 Nikons, but not quite. And neither of those two are as clear as my other friend's pair of Zeiss, which I believe set him back about $1200. But this is serious hunting glass. For my BOB I'm happy with my aforementioned Bushnells, which I think cost me about $19 new.

As far as brands go, Zeiss, Svarovski, Canon, Nikon, Leupold, or Steiner seem to have the best reputation and will certaintly get the job done. Whether or not you want to pay that much is up to you.