That shot looks a bit high to have hit the heart. Double lung hits are usually fatal within <100 yds. And that appears to be what you had. The muzzy 100 gr 3 blade is an excellent head and I used them for years, as is the Slick Tricks. I've never heard anything about the 75 grainers. I use Magnus Stinger 100 gr 4 blade for the past 5 years and have yet to have a deer go out of sight before expiring. I hit a buck on Tuesday and cut both arteries off the top of the heart. The blood was instantaneous and poured out like a spigot. He only went about 40 yds.