Some of the better less expensive low wing sport planes out there include:

Phoenix Models Dolphin .46 ARF (Tower Hobbies)
World Models Sky Raider Mach II ARF (Airborne Models)
World Models Super Sports .40 ARF (Airborne Models)
World Models LA Racer .40 ARF (Airborne Models)
Wingman II ARF (The Wings Maker)
Lanier Dart .40 ARF (Tower Hobbies)
Tower Hobbies Voyager MkII ARF (Tower Hobbies)
VMar Ramrod ARF (Richmond RC)
VMar Xtreme Stik Low Wing ARF (Richmond RC)
Sportsman Aviation Sport Stik ARF (Hobby People)
Black Horse Models Super Air .46 ARF (Hobby People)
Black Horse Models Travel Air .46 ARF (Hobby People)
Black Horse Models Speed Air .46 ARF (Hobby People)

All of these airframes are $99.99 or less in price, and are excellent sport planes suitable for any pilot who has mastered their 4-channel glow trainer. Gaining experience with any of the above airframes will help the new pilot learn more advanced aerobatics and better prepare that pilot for scale aerobatic planes like the Extra 300S or Giles 202 that the original poster mentioned.