Look at the airframe designs... you can tell that they will not fly the same. The Reaction has a smaller rudder and the fuse is short coupled compared to the Flash. The Reaction also has a straighter wing.

What kind of problems did you have with the Flash landing gear? I used the 8mm pins after the 2nd flight and flew it 250 times without a hitch.

If you want to keep it cheap and get a sport jet, you may want to consider the Dragon by X-Treme Jet. Here is a video I took of Jeff flying it at Buttonwillow:

[youtube]http://www.youtube.com/watch?v=vjOdUReaIpw[/youtube]