Biggest difference is the body shape. The H is essentially a super strat shaped Les Paul. It has a carved top with edging similar to traditional LP design. Depending on the year you're looking at, either 22 or 24 frets. I believe they're all neck through construction, but I'm not sure about the old 22 fret version. TOM & Stoptail bridge.

The F is a beveled flat top guitar, similar in design to a Gibson SG, or the new PRS S2 guitars. The shape is unconventional, but not extremely crazy. Generally super strat shaped, just with odd jutts and bouts on it. Bolt on square heel with TOM & stringthrough bridge.

They both have the same neck and scale stats, the Thin U. Depending on how old the H you're looking at is, it could feel different though. Some of the newer Thin U have more of a D shape that I don't like. Tastes and preferences vary wildly though. There is no right answer.

Pickups on either aren't worth mentioning. I think the LH-150s are very decent for stock pickups, but they're nothing amazing.

Comfort is also subjective, different shapes and styles work for different people and playing styles. I would say that the F would be more comfortable because it doesn't have as hard an angled edge as the H has. But it may not bother you much. The carve top itself on the H is very comfortable, though the edge takes away from that a lot. There's a trade off, unless you're just not picky. The bolt on block heel on the F will restrict upper fret playability to an extent though.
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