i have plans for a cri cri here, and a friend of mine has one 90% complete, with the 15 hp engine, they can climb at 250 ft/min on 1 engine! their single engine performance is better than most GA twins! they have minimal asymmetric tendencies as the prop wash from each engine is deflected by the canopy so with 1 engine out, the prop wash from the live engine being deflected counteracts the yaw tendencies, and also with engine so close to the centreline, there is little yaw anyway