I've got the Soba and like it a lot, especially for the flat ramps and rounded drops. Definitely the most comfortable bar I've ever ridden. I chose it over the Noodle to save weight, and because bars with center sleeves sometimes develop annoying creaks which, while not a safety concern for Nittos, annoy me. However, there are ways to eliminate the creak.
I didn't weigh my Soba, but I believe Rivendell has published the weight. It's certainly not significant to me, and I have greater confidence in any Nitto product than I do in the superlight wares from other manufacturers.
Is the Soba perfect? No--I don't care for the backward sweep much. It's neither more nor less comfortable for me than straight tops, but it does change the reach a bit, so now I wish I had a 1 cm shorter stem. I would also like a bit more downward angle to the drops. If using a quill stem, it doesn't look right to me unless the upper ramps parallel the stem, but at that angle on the Soba, the drops slope down only slightly. Finally, I'd prefer a bit (1 cm) deeper drop. But I'm being very picky here. I'm building up a new frame soon, and will be installing another Soba. I like it a lot.
Jack