I have shot several deer with both fixed and mechanical. I can not be a 100% certain, but if I did not get a deer the broadhead was not the point of failure. Poor shot placement or an oversight on my part was the issue. I had a lot of success with rage, muzzy, NAP, and G5.
However, this year I switched to a single right bevel 125gr Kudu broadhead. The first day this year I shot a doe at 15 yards hard quartering away. The arrow went in behind the ribs on the right side and exit the left armpit. When I field dressed her there was a clean slice through the heart.
After I shot the deer was the most interesting part. She went 40 yards and stopped. Looked around the field like she wasn't hurt, which made me question the shot. She took a few more steps, bedded down, and expired. I believe the clean pass through and a sharp broad head was the reason she did not make a 100+ yard death run.
The arrow was sticking in the dirt about 6-7 inches. I took it home, washed it, rehappened the broadhead, and put it back in the quiver. I plan on using it again this season if an opportunity presents itself.