markdam,
Believe it or not, I've had my Ultimate completed with the exception of installing the battery and radio for several weeks now. I plan on finishing it this week and hopefully flying it on the weekend. I have two props I am going to test (both recommended for the Saito 11) 15x6 and 14x8. A friend of mine had a Saito 100 on a Joss Stick (bigger and heavier than my 8.3 Lb Ultimate and this Joss Stick would go ballistic using a 15x8 wood prop. So, I am anticipating that my Ultimate will also be fine vertically speaking. I talked to Goldberg Models before selecting the Saito 100 and they told me that would be a good match for their Ultimate. I'll give you a report soon.
Jim