Hi Alex,

I use this prop too and like it a lot. Helps in smooth flying. I use it on the 14XL and based on the temperature and used amount of mAh i'm allmost sure it is to much load for the 13XL. I think you have to request Rasa (do not know if they have a contact, perhaps via Plettenberg) to create props for more fast revving motors. In the current line of available Rasa-MAG props there is not a prop with a load like a APC 20*13
See available props at bottom of page of Lorenz site:
http://www.f3alorenz.de/zb-rc-flug-z...rop-carbon.htm

You can find them at Plettenberg here:
http://www.plettenberg-motoren.com/german/Zuebhoer.htm

Plettenberg and Hacker also carry the Freudenthaler line (including a 20*13):
I do knot know however if this prop has the same characteristics as the Rasa-MAG props

http://www.hacker-motor-shop.com/e-v...&c=1909&p=1909

Regards,
Hans