OS is obviously a good quality engine that you cannot go wrong with. I've owned a few and they are great. I also have a Super Tigre G-45 with a Macs muffler in my Sig SE and it is the best engine I have ever owned. It idles perfect, transitions well and turns some excellent RPM's. After every flight, someone comes up to take a look and ask about the engine. I've heard about others having bad luck with Super Tigres but my experience has been great. It did require alot more breaking in thatn any OS I've owned though.