I for one think that a 4 channel plane is the way to go. I'm fairly new to this but at our club the instructors use 4 channel. I flew one of my instructors Avistar's a couple of times then bought my own plane which is an Apprentice. I flew it with my instructor and a buddy box. Things worked out very well with it but I noticed he kept telling me to use the rudder, after all, you paid for it
I soloed fairly quick with it and am very happy about everything. I also think that a bigger plane is better as it's easier to see. Good luck.