I have a Little Toni, which handles alot like a shoestring. It weighs 7.5lb. I agree you should power your model with the intent of how you plan on flying in mind. With a .61 its fun to fly. But thats about it. Everyone at the field knows what a Shoestring an toni are for. I have had a .91 on board for awhile now an I have to say I have enjoyed it alot more than a .61. Unlimited vertical. I have no clue how fast it goes with a zoar 13x9 at 10,600. But its way better than the 9000 with a 12x7 on a .61

I have found with an airplane like what you have its better to have a little to much, rather than not quiet enough. Just my thoghts on it