I upgraded from the 1007 to the prepro, 5509 - still the flagship unit in their range. (I already had the amps). My main reason for upgrading was to get XT32. But I think if I was going that route again, this time I would choose an AVR with preouts. Same facilities but cheaper. One issue for me is that I use Audyssey Pro so it would have to be an AVR that was pro-ready, but such beasts do exist.
Ahem... Keith, is the general functionality and menu structure still similar between the 1007 and 5509? One slight niggle that I have with the 1007 is how deep I have to dig into the menu to change Reference Level Offset [Setup > Audio adjust > Audyssey > RLO > toggle value > Return > Return?]. I like to ensure I'm using the recommended RLO for the content, format or source, so I do this a bit. Have you (or anyone else reading along) discovered an easier way of performing this adjustment?