The cons of a trainer is it has the self righting or slower roll rates.

Sometimes the model can get into a wierd angle closer to the deck.lol
Not having enough roll rates dosen't help in certain situations.

Generally a newbie trying to fly without an instructor, not getting enough speed
or altitude before banking the model, or pulling too much.
or encountering engine problems due to not knowing how to tune it properly at first.

A miss conception..it flys slower.
it's relatively, fast, fast when you're new.lol