Hi 425Cat, I asked a John Deere rep your question about driving the units hydraulically instead of electrically. His response was: Each row needed two separate drive sources. Electric was the easiest way and hydraulic would be near impossible.
Here are a few answers to your questions from a John Deere rep:
The ExactEmerge planter will be available in 1775NT or 1795 CCS models, which are sold with 15-, 20-, or 30-inch row spacing.
John Deere Seeding releases prices when you can order the product. You can order ExactEmerge with Deere's early order program coming up in early summer, so this is when prices will be available.
I asked a John Deere rep your question and he said: John Deere won't have a factory solution, but ExactEmerge was tested and compatible with Smartbox.