Hi Amorinthe.
May I be the bearer of bad news? Well not news, but just my personal, unrequested

, opinion.
Seeing as how our 3 DP's (in the 13G) are 'schooling' all the time, I'd now hesitate to have a 1 DP set up. I was thinking about it back then, but now that I see them in action, it wouldn't feel right to have one on his own.
They're really buddying up and doing their 'spies on a mission' impression. I just can't picture one on its own now. Perhaps am totally off, and they're perfectly fine alone, as say the books, but, you know.
I do think they like quite a bit of room too, from the way ours are behaving.