Just to add a response to the questions about size and ease of use sitting on the couch and in bed. I'm a pretty small person. The 12.9 certainly isn't something I could stand around and hold in one hand all day (although without cases on it, it's just not that heavy), or hold in one hand to read on the couch, but I sit against the back of the couch with my legs propped up and use that way to play games, read, etc. I do the same if I want to use it in bed. I keep my ASK flipped back and use the on-screen keyboard when I do that. It would be even lighter in my lap if I'd just pull the ASK off. When I know I'm going to be typing a good bit, I'm usually at the table with my ASK (which, by the way, I LOVE), but I use it propped in my lap at some point every single night.
Now granted, I don't throw this thing in my purse when I'm gonna be out and about running errands, but I doubt I'd do that even with a 10.5. I think the only thing I'd be likely to haul around would be a mini, and I just haven't found the need for - my 7+ works for killing time if I'm in a waiting room or sitting still in traffic; stuff like that. I DO take this beast with me when I travel, and it's just not a big deal to throw it in my overnight or carry-on bag and haul it.