Typical power to weight ratios for RC models.
11-15 watts/100g Minimum level of power for decent performance
15-20 watts/100g Trainer and slow flying scale models
20-24 watts/100g sport aerobatic and fast flying scale models
24-29 watts/100g Advanced aerobatic and high-speed models
29-33 watts/100g Lightly loaded 3D models and ducted fans
33-44 watts/100g Unlimited performance 3D models