Well it's been 6 years since SES rebuilt my 717 engine. Got my engine back. Ran about 40 gallons of fuel and engine stopped. SES said my oil injection failed even thou the injection unit bench tested per spec. Got the warranty engine rebuilt back. Converted to premix it ran for 15 minutes. Sent back again. This was the engine that ran for almost 6 years till it lost compression. Decided to rebuild it my self this time and this is what I found on the tear down. A WSM piston on the front and a SBT piston on the rear....? Plus 2 different types of rod clips. WTF..? I know some people have got good results from SES, not me. Extremely disappointed that during a so called no fault 2 year warranty they would do this with mixed sub parts. Just be careful