Root should probably be discussed on another thread but,
approximately how many solo flights do you have under your belt, how long have you been flying and how old are you?

Depending on what plane you want to buy,, the size of the model isnt as important as "cost" and "skill level required to fly". SOme larger models are actually a heckuva lot easier to handle than a 60 size model, its just that there is an additional $$ risk with bigger planes.

You just dont want to go spending a bunch of money on a plane you are not yet equipped to fly.

If you trust the judgement of the guys you fly with then take them their word. If you dont and ar confident of your skill and old enough to make your own decisions then do what you want. Old enough to make you own decisions meaning you are an adult paying your own bills and making your own way.

By the way those"skills" you mentioned.... stall turn, split ess, and imelmman turns are not survival necessities but they are handy skills to have and should be part of your basic training package just to teach you simple maneuvers to demonstrate your basic skills.