RE: OS .10 LA
should fly very nicely!
the plane i learned on had a similar 20cm (8" ) chord, 15cm more span and weighed over 1200g (45oz)...all this flew very well, even too fast, with a muffled enya .11cx which isn't a whole lot more powerful than the os .10....landings (dead stick of course) were'nt too much fun at that weight though..
the os .10fsr i had also did a decent job flying a VERY overweight (48oz+++) and draggy sig scamp
7x4 MAS or APC will do a good job
dave