Ari, I have flown two of the Top Flite DC-3s for the same gentleman. The first one had OS 40 LAs while the second one had OS 25 FXs installed.
The OS 25s flew better than the 40s and generate enough power to make single engine go arounds from botched landing approaches. Either airplane will take off in less than 100 ft on hard surface runways. Landings take about 250 plus from touch down to roll out. Just wheel them on like the real thing an all will be well.
Both engines fly the plane best at half throttle when cruising. Full throttle looks like an old pattern ship roaring around in the sky.
Landings are real straight forward with or with out flaps.
The most important things are a true airframe, proper balance and engines that idle and come off of idle in a reliable fashion.
Top end rpm is not that important. It is better to run the engines toward the rich side than risk a shutdown in flight from a lean run caused by tweaking the last rpm out of them on the ground.
For their size I think that they are good performers you should have a good time with one.