I have been at this archery game for a long time mid 70s.Have killed 70 big game animals with a bow and a ton of the smaller game.I have used longbows recurves and compounds.If a arrow flys strait and hits the target strait helps a lot with penatration. Slow heavy arrow have been killing game for hundreds of years if not thousands.But in the last 12 years archery has made its biggest advancments in speed and arrow materal(SP)with these and great broad heads penetration on game at bow range is not a problem if you bow is tuned properly(arrow flying strait)I have seen more penetration from arrows made of carbon and with broadheads like muzzy, T heads.Than with aluminum from compounds or recurves.A fast carbon arrow (250 fps to 300+)with a good sharp broadhead will kill any animal on earth as long as proper shot place ment is made.The most important thing is getting a arrow of your choice to the lungs and heart of the animal.Hope my ramblings have not bored to many I just love bows and bow hunting