I personaly would recomend the ATrag program, Ive used it a few times, and it works amazing. It allows you to build and load data for multiple rifles (barrel length, twist, cal., bore height) and diffrent loads (bc, velocity). Imput weather conditions, moving target data, range, and it spits out a solution in mils, moa, clicks or feet, yards, meters. It also calculates range, using the target size and mil reading. As far as the kestral, i never leave home without one, it might not give you the wind down range, but it will give you everything else and some kind of an idea of what wind looks and feels like. Wind is just something that takes experience to read. The kestral is a tool i used to learn wind.