I started with Master Airscrew K 16x10 and before i'd even flown it i'd gone to a Master Airscrew Classic (rounded tips) 18x8 and due to the noise it was producing i went up to master Airscrew Classic 18x10. The CRRC 26R produces a quoted 3.1hp so check your hp out before you go up to this size but i have to say the performance was great and the noise much reduced........then i crashed it.......but it was not the props fault.