Hey Rumble,
I have two MDS engines, a .78, and a 1.48.
Both are ringed engines, and I have been breaking in the .78 on the bench today.
I have ran four tanks(10oz. each) through the .78, and I have been keeping it very rich(ringed engine, remember!)--but, it runs GREAT!!
It idles very well, has not quit for any reason on the bench until the tank ran dry.
I am hoping this baby just keeps on improving, I just started to lean it a wee bit on the 4'th tank, am being careful to do it slowly!
Haven't ran the 1.48 yet, but plan on doing the same thing--nice long RICH breakin---going to put it in a Lanier Edge 540T!
Best to 'ya,
Pud