I am running a BME 0.90 on a Mojo, previoulsy it has been on a small Waco Bipe and a Cub. Try the 13" prop first by all means but you will most likely prefer the 14" for your cub.

THE BME 0.90 IS A GREAT LITLE ENGINE.

I have also run the Chinese 15cc's (RCGF 15 and JBA 15 as well as the NGH 17) and they are not a patch on the BME, not even close when it comes to real life performance. Don't be fooled by the "Spins xxx prop at yyy rpm" claims on how the others are sold.
Have a read through the threads on the others and you will see why NOT to buy anything from those "designers" People have a lot of issues with them in the range where they actually get flown.