I've been scouring this sight and others for a good PC based ballistic program. I have infinity but it has drawbacks. I only need exterior and need to be able to input G1 or G7, twist data,etc. for spindrift, and the other basics - temp, alt. etc. I was going to order Patagonia but frankly, both Lens description and the website sounded a bit complicated. Can a contractor of average intelligence figure it out or are there simpler ones?