Hi John,
I've had the same question since I'm in the process of filling in a gap as well. I would have gone to another Titleist Thursday for a fitting and comparison, but I'm out of time to leave for a long period during the day. If I were you, I would check out the Titleist Thursday www.titleist.com/thursdays *they'll have all the shafts also, I'm sure.
Anyway, instead of that, I've gone from store to store in different days to compare the H1 & H2 specifying the same shaft on both. What I've found the biggest difference between is the H1 gives me a higher ball flight and I'm able to land softer. On the H2, my ball flight is a little lower- a little more penetrating ball flight so my ball rolls more. Also, taking a little divot with the H2 works a little better or more satisfying in feel- I could also imagine I'm putting more spin on the ball playing it that way, and the shape is more defined.

Anyway, for what I'll be using it more on, I opted for the H1 and kept it simple- I just sent for my order last night.

The website describes the two just like the result of my testing- but I had to try it and see for my swing...so I know exactly where you are coming from.

Good luck on your search!

My 716 AP1s start with a five iron which I hit around 180. I carry a 816H1 21*, 915h 17.25*, 913F 14.25, and a 910D2 11.0*. These fill the gaps well for me. Am a senior (69+) and a great drive for me is 250. I suggest going to see a fitter and take the 4 iron and the 5 wood with you so he can compare, and get you set up with the right shaft and head combination.

Another difference is from a cosmetics standpoint. The 816 H1 has a bigger footprint than the H2. H2 is more compact and if you prefer a "cleaner" look (no better adjective came to mind) than the H2 is the go to. At their launch last October up here at the TNFC (Eagle's Nest) I saw not noticeable in striking from one to the other.

Alex