Right, it's one of the rare players does both.
In terms of how its built -- well, it's a bargain player from China. The only way this gets around the Blu-Ray region spec is because it's flying under the radar. That said, you can scroll through some of the message board posts like this and most people seem to be quite happy with it --
http://forum.blu-ray.com/showthread.php?t=216607
The Seiki and the Insignia you own are basically the only options you have unless you want to spend $500 for an Oppo. It won't change either because the licensing requirement for Blu-Rays mandates that they're locked for a specific region. (Though I do have a Panasonic that'll play most out of region Blu-Rays, just not the PAL 1080i50 ones -- but it cost $100).
Really you should just bring your Insignia down on your next visit and I can put the firmware in it that'll enable it. It's essentially the same player as the Seiki (with the added benefit of Netflix and such, which the Seiki doesn't do), and the code that opens up the other regions functions the same way (numeric code you put in each time you want to watch a disc from a non-US region).
The Seiki is basically a bargain-end player you'd use for out of market Blu-Rays and DVDs...it has no internet capabilities, it doesn't even have sound outputs beyond HDMI (if you need optical audio out for an older receiver, you're stuck)....so if you're not interested in the region free angle, there are much better and better-constructed name brand players on the market for the same price.