Hey OK.....
I have a ST3000 on my 1/5 decathlon and love it,,,,it has a 28 ounce tank and will fly for 20 plus minutes with fuel to spare....I run 5% which is about $11 a gallon, and am very happy to invest this much for what I get....everything (including carb) is original and would'nt trade it for anything. I use an 18x10 Topflite wood prop (fyi) Engine is very reliable and starts/transitions/and goes full power without any "coughs" or sputters, which is very rare from what I understand....I also use a type "f" glow plug....