552,
The TRP just has a bit more to it than the Loaded or Mil Spec. TRP comes checkered(machine cut) which isn't bad at all. Also it has a adjustable BoMar type rear sight that has been located about .250" forward than a standard BoMar cut. This is to keep the blade protected and such. Barrel is a bull type with a reverse plug for the guide rod. Oh yeah, also comes with a magwell, which I later replaced with an S&A well. It's hell trying to find a holster for this thing though. I'm a southpaw and I wanted it for work so I'm waiting.
Eventually I'm going to try and pick up a Loaded model Operator as well and when I have more time checker it and add a S&A magwell to it and such. I work on other people's guns more than my own these days.