The 2500 was 25 CC glow engine, ran on low percentage nitro and less oil than other glow engines. A friend had one in a Akrobat II that was about the same size as the US 1000.
The Arkobat II had a strange life, a friend's fellow coworker copied the plans and started the build, cut the ribs out, he then gave it to my friend, he decided he could not built it and gave it to me. I built the model and order a cowl from RC City, they sent a cowl for a 33% Laser. When I called and got the new cowl on the way, I decided to keep the Laser cowl because it was so nice. I finished the plane and didn't have an engine so I gave it to another friend, he bought and installed the Super Tiger 2000 or 2500, not sure what one. He flew the plane for over a year and ask me to test fy it one day after making some changes,after several minutes of flying lost control and said I don't have it, friend said "oh crap, I forgot to fasten the battery down!"
After another year I found a set of Wayne Urley plans for the Laser at a fly in, $15.00. First foam wing build, first wing tubes built, Quarda 50 with Purrpower muffler, later switched to a G62.