For the last year I have been reporting stalling problems with my MDS 148. The only certain cure has been an on board Glow Driver by Telco. I have tried three different makes of carb and every possible cure to the fuel system, but the thing still switches off the ignition in flight. On the shelf now replaced by an SC 120 Four-stroke. Not as much power but never stops.
My old Wot 4, has also suffered this week from it's MDS 58 switching off resulting in a forced down wind landing. All my MDS engines ran perfectly when new, but when run in they stop in flight. The new carb called P2 has not cured the problem. I watch other club menbers and now realise that saving a bit on cost over an OS can be expensive. My club mates with OS engines and my own OS four strokes never stop and are easy to adjust.