I had a OS 91 (apc 15x6) and a Satio 82 (apc 14x4w) on my UCD 46 and thought they were both a good combo it.... i had to put the battery as far back as possible with the OS91 to get it to balance

I wouldn't bother with expensive servos unless you already have them.... i used JR 537's on mine and never had any problems, like Barry said, i would use 4-40 rods on the elevator and rudder and beef up the landing gear too.... one last thing, if you put the wheel pants on and your LG does fail, the wheel pants will poke a hole in the bottom of your wing on both sides