A buddy of mine has used them religiously since they came out, and
swears they don't spook deer, but NEVER see's mature bucks.

Oh yeah, he also chain smokes on all his hunts, and hasn't washed his scent lok jacket, which he routinely wears to work in cool weather in at least 5 or 6 years. So that might explain it!

I'm going to pick one up this year. I don't have any concerns at this point.