Well, they where going to give me a 550, but there aren't any in stock or available at their major retailers across Canada (my online perusal confirms this), so a 540 it is.
From a review I read, the only difference is "the 540 series is a stripped down version of the 550 that sacrifices 2 HDMI inputs (I'm pretty sure it's actually 1 HDMI and 1 component) and any network capability."
Seeing I can work around the one less component input, and I don't care about network connectivity, I'm happy. Here's hoping it has a nice picture.