1 It has two servos for the ailerons
2 yes the saito 100 will be fine
3 I added wheel pants from a venture 60 and a 60 size Klett tailwheel assembly can't remember changing or modifying anything else. Correction on that. The rudder and elevator servo pushrods are nylon in a tube. and they expanded and contracted so much during the temperatures changes during the day. the trim had to be changed as the weather changed. So i used 4-40 metal rods thru the stock outer tubes and got rid of that problem. any other questions just ask.
4It is an excellent flyer
Dennis