I wouldn't say success, but I've used scents of different types (scent wafer/leaf, hanging wicks, drag line, gel or spray on branches, herd in a stick...never tried buck bomb type sprays or scent heaters) in the past and didn't see any negative effects. Mostly I just saw no effect from the scents. I only saw deer react to it a few times by sniffing the ground or the branch it was on, and then walk on. So I wouldn't say it helped or hurt those hunts.
For decoys, I've used a 3D target a few times. Again, wouldn't say it helped or hurt those hunts, but never had a mature buck come in view on those hunts. One time, I didn't get the stakes in the ground far enough, and my decoy decided to take a nap. Another time, I couldn't get the stakes in the ground at all, so used it as a bedded doe in the middle of a clover field. Had a young buck walk within 30 yards of it watching it the whole time...didn't spook, but didn't put him where I would need him for a shot either (if I wanted to take it). Another time, it did stop a doe that had run into the clearing I was hunting, but then she ran off. I would say that was neutral to positive as well, as she ran in and ran off, but stopped long enough that I could have possibly got a shot off.