Here's my two cents worth....
Prop? If you're using a .46-.51 two stroke I would use an APC 12.25x3.75" or 11.5x4"
*** see for yourself what folks are using...
http://www.rcuniverse.com/forum/m_20...tm.htm#2095602
Y-Cable? Not only does using a Y reduce your options for flapperons/spoilerons, it also reduces your chance of hooking things up wrong. If you're new into the sport you could use every "safety net" you can. Ask fyrwalker! He knows first hand what I'm talking about!!!