You still have to tune the bow regardless of their claims. I had some in 100gr and I could not make them fly, but because I shoot a WB I had to weaken the spine by using 125gr heads. Thats when I lost interest in the Talons and went with Montec G5s. Of course I'm no archery expert, but I can still figure out that their claims of picking up your bow and shooting is nonsense. Still they might be good broadheads, just not the cure all wonder weapons of the future. Besides Montec makes practice heads that fly just like the real deal.