I have mixed feelings on this topic. I saw 3 deer that I shot go down within my sight, this year. Of the two that didn't........1 was a complete passthru.....(see 1st photo)

The other was a shoulder hit that penetrated both sides of the deer......but did not get full arrow penetration.........(see 2nd photo)

In both instances......the blood trail was NOWHERE NEAR what I would expect for an animal that died inside 40 yds and 110 yds, respectively. The trails were sparse.

I use the muzzy 3-blade in 125gr. I've recovered every deer I shot with them......so I won't be switching any time soon.