I hope you mean a couple of models of TeeRex and not just two discs...
What is special about them?
I have been working on "improving" the TeeRex, so now there are 6 different mold variations to work with. Add to that, three different plastic types, and we have some room to play. As we are currently running DX TeeRexes, I don't think I would opt for any DX types. Most likely the buffed up (more high speed stable) non X version in some type of Star or Champion.