Leo - my first four stroke setup was a Flite-Streak with an OS 20. It worked very well, flying on 52 foot, .012 lines.
Not knowing how little fuel the engine used, I made my first flight on a 3 1/2 ounce tank.
I was concerned and hoped that it would quit before sundown!
Although I have not flown the Magnum 30, when I bench tested one, I found that the power was not what I expected. It turned a prop just a tad slower than my OS Surpass 26. Your results may be different.
Bob Z.