IME (Like IMO, but this is from experience)
Both brands are overpriced for the quality you get and you will find better product for far less money. Given the choice of the two, I would go with the Marantz over the Runco in a second. Yes, I think Runco looks good, but they have poor reliability in my dealings with them, and tend to be far more expensive than necessary.
Marantz is just more expensive than necessary, but their projectors are pretty darn solid.
If I were in that price range, I would go with Sim2 in a second. I recently installed a BenQ W10000 and it was phenomenal. The JVC 1080P LCoS projector is also incredibly highly rated and comes in around $5,000.
The main reason anyone goes Runco or Marantz is because some specialty home theater custom shop is padding their bottom line... Look for $1,000+ in cabling to go along with those types of projectors. Way more than necessary, but typical for custom shops.
