i have used both the three and four blade models religiously for the past 2 yrs.they leave one heck of a hole!only trouble is that every deer shot the entire ferrule was bent.not really bad but enough that you couldn't use it anymore.that's not a problem as long as they do the job,but last year i shot a big buck(about 230 on the hoof)and i hit him high and directly in the shoulder bone.the sidewinder4 only went in about 2-3 inches before shearing off at the base of the shaft.what it looked like to me was that b/c there were 4 blades they had to take out more material to make the groove that the blades rest in.i did get that deer with a quick follow-up shot but once bit,twice shy.so i went back to the nap shockwave.never had a problem with those.not as big a cut as i like but very dependable.