I have noticed that most fixed blade heads fly to the same spot all have 1 1/8" cutting dia. or 1" cutting dia.
the mechanicals offer much more (all most 3 inch cutting dia. in some cases) cutting diameter and fly like feild points. good name brand heads will work every time so long as you clean'em really good after every shoot. espechially if they take a nose dive into loose soil. keep the blades sharp, keep the iner workings clean and the will serve us well. I was told this by a hunter/small archery store owner this once and he turned out to be right. todays mechanicals are not junk in most cases. for instance I got a few of NAP's mechanicals (both spitfire and the other) they were onsale at wal-mart (only 10 bux for 6 a pack so I grabed all the had) and they both work really well. there is another brand that was even cheaper (eastman outfitters I think was the name) and they worked great on the squirel I shot. they cut 1 3/4 inch so it might have been a tad over kill but what the hey.