The LT-40 is within a couple of inches of most 60 size trainers. But, it's light enough to fly well with a 40 size (less expensive) engine.

When I decided to start flying, I wanted an ARF trainer. I went with a Hobbistar 60. If the LT-40 ARF had been available at the time I probably would have chosen it due to the fact that a Thunder Tiger 46 would be plenty of engine. I ended up with a Thunder Tiger 61 which cost almost twice as much as the 46 did at the time.

I do believe big trainers are easier to learn on than smaller ones. That's mostly based on being able to see them better.