Hi,
Neat airplane for the price. The OS 1.08 should have plenty of surplus power.
As you build, remember that with this kit a significant part of the wing's torsional stiffness comes from the tight, film type covering contacting and sticking to all ribs, main spars, and the turbulator spars in the forward section of the wing. I found that the higher shrink temp "money-coat" works best. I tried some premium "fabric" style once and I had to take it off because I was seeing some wing twist during high "G" turns - really strange flight characteristics show up when that happens!
I built the last one with a Decathlon fiberglass cowl that I found gathering dust at a local hobby shop. The width and the height of the cowl sides were correct and all I had to do to the fuselage was build a new fore-deck to match the top curve of the cowl and "round" the bottom edges of the fuselage sides. I also trimmed the supplied canopy to fit the new fore-deck curve. The slightly convex fore-deck and cowl looked good with the stock turtle deck. No one seemed to know for which kit the cowl was originally designed. But, you can probably find a plastic or fiberglass cowl from one of the after-market suppliers by using the Four-star measurements without the standard "cheeks".
The Saito 1.50 in the nose was side mounted and supplied lots of power.
This time I mounted the rudder and elevator servos in the fuselage sides back at the tail and this really improved the control. I used a servo in each wing for the ailerons with the servos mounted so that the control horn fell at the mid point of the aileron's span. I enjoy flying my Ultra-Stick in the "crow" mode. However, the Ultra-stick does not have the same clean aerobatic performance as the Four-Star. So, as an experiment, I used the inner 10" of the ailerons to make flaps that were each driven by a separate wing mounted servo. I have two "models" programmed in my TX for this one aircraft. One is to permit the crow function and the other couples the flaps with the ailerons. It flies as I planned. The crow works great, but with a reduced roll rate. With the flaps coupled to the ailerons, the roll rate is back at the normal Four-Star rate.
I use a 3000 MAH NiMh at 4.8V because of the seven servos.
One note on the "crow". It is very important that the servo linkages and the positions of the control horns be symmetrical right-left for both the ailerons and the flaps. I found the programmable servo functions of my Futaba 8 channel to be very useful.
Have fun,
J