I would go for 23D over 34D. But I am only 175cm tall. Some taller people have stated they find the bulkhead row has less legroom, which is not something I have noticed personally. The bulkhead is the perfect distance away for me to place my briefcase on the floor and use it as a higher footrest than the Dreamtime seat offers.

But for Skybeds, its a bit early for me to tell. But really, there is not going to be much difference. To me the main difference is the ability to use my briefcase footrest and nobody reclining into me, but the skybeds overcome that advantage!