yardage pro "legend" question

[stinky]

hi all! I'm going to buy a rangefinder soon and the i have all but committed to buying a yardage pro legend. The only hang up i have is that somewhere through my research, someone said that they were too sensitive in thicker cover and that the zip mode wasn't effective at close range. Has anyone used them? and if so, what did you think?

 

[Black-tailed bandit]

They work great untill you get in to thick fog.

 

[Hank Hunter]

is it just me or are they supposed to work when you cannot see your target in thick fog lol