Thanks Bill. I was waffling on one vs two until I saw your posts. I don't yet have any real experience with it, so can't say much about performance, although automatic levelling is indeed very convenient.
The only possible negative which I thought about after the post above, is that with float valves, as compared to valves that incorporate check valves, there may be some leak down during use. I don't know if this would be an issue or not. In my case, when using the brush hog, which is not that often really, I put the float section on the top link, and use two valve sections with check valves in them for the lift cylinders. This holds the lift arms in position forever...
Still...I really would like float on both lift arms at times!