Buying an ignition box

I want to buy a msd ignition box tonight, and have found on amazon a msd 5200 box for $100, and a msd 6200 for $170. I am using an amazon gift cert, and have to shop through them. Is there a functional difference for my 61 fhead between the two boxes? I have regular points now, and am willing to spend the extra money, but don't want to if the difference will never even be noticed...

Let me know what you think soon, my fingers are itching to buy it soon...

 

I bought a used 6a box (6200 series). I like it a lot but didn't know if it would help or not at the time. I wanted to buy a box that everybody wanted in case I needed to unload it. Everybody wants a 6a, nobody wants a 5. I like the capacitive discharge concept and don't care to spend money on an inductive box.
I don't know if there's any functional difference for an F head. If you have the $, I'd buy it.
I use a stock coil (as accepted by MSD) but use 8mm silicone wires (as recommended by MSD) and run a 0.055" gap ... it'll burn anything. With the Weeber carb and 2" exhaust, I get 15+mpg in the hills. And, it'll GO when I need it to (at the expense of fuel, of course)

 

If you go with a Mallory Hyfire, you can have a digital box instead of analog for less money. Hyfire pumps about 530 volts to the coil, MSD about 480. All CDI boxes are multiple fire up to around 3300rpms.