Hey there,
In your shoes, I'd probably get the MMG instead of the 12's. They are slightly smaller and have almost exactly the same specs (better high frequency extension but bass down to 50hz rather than 45hz). They are also cheaper @ $550/pair brand new direct from Magnepan. The MMGC is also available direct and I think it's only $299. It's also smaller than the C1. I'm pretty happy with the way my DT speaker blends with the 1.6's. I think the argument that the center speaker has to be "voiced" similar to the mains is mostly BS so you might want to just focus on what fits in your living space and THEN narrow your choices based on sound.
As for the pre-processor, the 990 is hands down the best deal these days. I'd definitely choose it over anything from NAD or Rotel. As for the Sherwood Newscastle...I forget the model number, but their pre and the Outlaw 990 are basically the same physical hardware with different software. So if it was me, I'd probably just buy whichever one is the cheapest. When I first picked up the 990, I thought Outlaw would be Johnny-on-the-spot with firmware updates for the 990, but that hasn't been the case. Read the forums and check on the various features/bugs as that may also affect your choice of Outlaw vs Sherwood Newcastle.
For the power amp, 200wpc might be overkill in such a confined space. Even if you can stand the sound levels, your neighbors might not. 8-) I've been pretty happy with the Outlaw 755 (which is no longer available). There's always the Outlaw 7500 which should be ample to drive the MMGs or (hold your nose) the Rotel RMB-1077 which would probably put out over 200wpc into the Maggies' 4 ohm load, use a LOT less power, take up a LOT less space, and generate a LOT less heat. If it's within your budget, I'd probably go that route even though it's a little more expensive than the 7500.
Lastly, you'll want to invest in a nice subwoofer. The Outlaw LFM-1 is a very capable unit, though I'm not sure you could easily "hide" it in a small apartment. 8-) If you end up wanting to go this way, email me offline. I've got an extra one (and I've got a MUCH bigger room) that I leave off most of the time. There's also the smaller LFM-2. I've never heard the LFM-2 myself. The LFM-1 will rattle your fillings out without breaking a sweat. 8-)
Hope that helps.
Cheers,
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