I just got off a 777-200 with SpaceBeds that brought me to JNB from SIN. Here is a recap of my experience.

The seat is very comfortable to sleep in, but sitting and eating/working is a little tricky. I was able to find a comfortable position to work on my laptop with, but a good eating position was impossible.

The electric controls are weird, and take time for you to understand them. Also, the massage function on the chair is a nice toy, but I think the one UA has on its C seats is better.

Another issue that you need to get accustomed to is the lack of personal space. I dont know if its only an optical illusion, but I felt that with the old Ultimo seats I had a little more distance between myself and the person seated next to me.

Also, when you use the seat in any sort of recline position, there is no space to put a bag or briefcase on the floor. This adds to the cramped feeling. I think that getting the seat blocked next to yours is a real plus.