Hi, greatdane! I'm kind of trying to study both at the same time (along with the Gaian and the Universal Goddess). Let's hear it for short attention spans!
I finally got my twigs (ogham set with twigs from each tree from an eBay seller), so I've turned up the studying so I can play with them soon. I like the tree connection and did a good bit of studying a while back for tree stuff. Now I'm basically memorizing the letter signs and names to go with the trees.
One difference for me is I find the actual writing of the ogham symbols kind of tiresome. And reading them, too. Is it 4 or 5 lines?? In contrast, one of the things I really like about runes is the economy, even elegance, of the signs.
Although I haven't done much ogham readings, one way they're similar is in number of items/cards. 24 or 25 runes and 20 or 25 ogham staves. I think if you draw, throw, whatever more than 3 or 4, you're using too many for a clear reading.
I find runes very down-to-earth and easy to read, just read them like a three main word sentence. I'm thinking ogham might need more translation--letters to trees to meaning to applying to subject.
I'm going to play with my twigs today (I'm on vacation!!!!!!!!), and I'll let you know how it goes!