Having your instructor agreeable to what you are flying, in regards to plane, engine and radio is preferable for sure. At our club we've seen plenty of new guys come along with cheap equipment sold to them by various local hobby shops and they wonder why they have trouble or can't upgrade, etc.

Talking to the instructor and other guys at the club is worth doing particularly since you are likely to ask them for help when you have trouble. If you've asked them, and gone against their advice, they may be less able to help you then if you go for their advice.

At the end of the day, however, it is YOUR plane, YOUR equipment, so you have to get something you are comfortable with.