I'll say it again, I track deer with a dog as part of my business, & keep a record of what the deer is shot with & where it was hit if recovered. Mechanicals are responsible for more lost deer than fixed blades hands down, regardless of where the deer is hit.(including gut shots) This is mainly due to poor penetration, & or weak construction.
My opinion is completely unbiased, & is based solely off of records keep from 10+ yrs of tracking deer, shot by a variety of people with varying levels of experience, & equipment setups.
Bottom line is....if you hit the deer good it doesn't matter what your shooting, but if you hit him bad, & everybody does on occasion, you'd better be shooting a sharp, strong, good penetrating head. You can only find all three qualifications in a fixed blade head.