The sims are really games at heart and don't want to make it as difficult as it really is. The model flight sims do have good uses but they also have their limits, I recall one chap in my club telling me he could do rolling circles, turned out he meant on his sim, and he could, I saw him do it, yet in the real world he couldn't fly a level turn never mind a rolling circle!

No plane can do a "proper" turn at 90 degrees of bank, it is physically impossible. By "proper" turn I mean a balanced level turn, not an aerobatic knife edge manouevre. Any plane can do a balanced turn at 90 degrees of bank but it won't be a level turn - a level turn means maintaining height. It must lose height. The wing is what holds a plane up. When banked the lift force is angled away from vertical, that's what makes the plane turn, but there is not enough vertical component so the total lift must be increased. That's why you pull back on elevator, to increase the angle of attack and get more lift, it's also why the stall speed rises when you turn. But at 90 degrees of bank, all the lift force is pointing sideways, there is no vertical component, so no wing lift to hold the plane up. It must either lose height, or the pilot goes knife edge to get lift from the fuz, but for those of you who have no experience of full-size aerobatics, believe me it is most uncomfortable for those not used to it, and the drag rise is a heavy penalty. It is potentially dangerous since it is up elevator and lots of rudder, again the controls for a spin/flick, so should only be done by experienced pilots with a suitable model and safe height.