I have shot 2 deer with them. First was CLOSE range (2 yards), massive damage as you would expect. Last year I shot a deer quartering towards from 80 yds with my old Traditions Deerhunter, the 300gr version driven by 80gr 777. Keith Nose traversed the chest entering front right and ending up somehwere around the stomach....looked long but could not find the bullet though I'm sure it did not exit. Had 2 sets of entrails in the wheelbarrow though (great hunt!) so it was hard searching.
Despite the design and the perfect shot (hit both lungs and liver), the deer ran over 100 yds and only went down because it tried to cross a ditch it could not climb out of.
Basically, I have killed deer with many different ML bullets (Hornaday HTP, PR QT250, PR Duplex DC 195, 300gr Keith Nose, 250gr Shockwave, 200gr Shockwave, Buffalo Ball-et) and have seen nothing significantly different between them in terms of how quickly the deer went down....some fall in their tracks, some go 100yds despite massive damage and perfect placement. The Keith Nose do more damage to target backers but I cannot confirm this is significantly more than anything else on deer yet. I hope to notch up a couple more this year to boost the sample size.