RE: sig astro hog engine?
Mine was built per plans. It weighed 3.57 kg (7 pounds 14 ounces) with an OS .70 four stroke. It flew very well with that engine. My brother has a .91 four stroke on his and it also flies very well.
I have an ASP .61 two stroke on one plane and would not hesitate to use it on an AStro Hog.