Super Tigre engines are now made by GMS, who also makes their own line of engines. They also used to manufacture the Tower Hobbies brand engines. I really like the Chinese-made Super Tigre engines; the story has it that the family that owns Super Tigre had the factory tooling moved from Italy to China when they first moved production to Asia. I don't know if it's true or not, but it's a good story.

The Evolution glow engines are made by Sanye, who makes engines under their own brand name as well as Magnum and ASP. Evolution gasoline engines are reportedly made for Horizon Hobby by MVVS, and have a wonderful reputation as some of the best gasoline engines for model aircraft that you can buy.

Another major glow engine OEM in China is Jiang Blue Arrow. They manufacture their own JBA line of glow and gasoline engines as well as the SK line of glow engines carried by http://www.kangkeusa.com and http://www.bj-model-engines.com/home.html at this time. JBA is also said to manufacture the VMax engine line for http://www.richmondrc.com in Canada. They probably were also the OEM behind the old Tiger Shark line of glow engines, but that is a guess on my part.

If you were curious about other engines made in free market economies, you could add Enya (Japan) to the list along side of O.S. Max (Japan) and Thunder Tiger (Taiwan). Enya engines can be purchased directly from the company's website at http://www.enya-engine.com where you'll likely want to select "English" as your preferred language.

If I were in your shoes, AJ, and owned a Super Tigre GS-45 and an Evolution .46 NT, I'd use the Super Tigre GS-45 and try to sell the Evolution .46NT. The Super Tigre is the superior of the two in terms of quality and power.