OK, I need some advice,

I have an plane with the JR quattro, I'm starting to think of my next plane and my next remote.

I have decided to go with the JR 6102, But not sure if I should get the same channel as my quattro? What are the pros and Cons to having the same channel besides the obvious, You can fly two planes with one remote and you limit yourself to one channel at the field...... are there other issues I should think about before I make my purchase?

Second Question:
I'm planning to buy the Seagull 300s ARF (63 inch wingspan)
I guess I would like to here some opinions on the plane from those of you who have it and what is a good engine for this plane? The LHS said if it recommends a .61 Then put a .75 or bigger in it or I will be wanting more power. What do you have in your 300S and how does it run? What would you recommend?

Thanks for all the advice!

Michael