Sounds like you the prop is for a 46 size engine and the plane is a trainer? If thats the case the nylon prop makes a better choice. If you bump the runway with the engine running, the nylon prop will probably be ok. If a wooden prop touches anything with the engine running it will mmediatly break! Also a 11-5 will give you more punch if you need it to get out of trouble than a 11-6 so I wouldn't bother changing that either. The most duarable props for training are the black Master Airscrew props. Less durable, more expensive, but more efficient are the APC brand grey props. Wooden props are about as efficient and the same price as the APC but are very brittle. Hope this helps[8D