RE: 4 inch versus 5 inch fletching
It looks liek your using a fallaway so I wouldn't worry about it. I woudl shoot either. I will say in general the 4" is all around the standard for carbon arrows today. I woudl base my fletch length more on broadhead style than shaft length. If you are using broads with a 1" to 1"1/8" cutting diamter you can shoot the 4" without any problems. With mechanicals the 4" is fine. If you shoot larger fixed blade broadheads then I would go with a 5" fletch.