The Hobbyzone Champ is the easiest to fly airplane sold by Horizon Hobby. It's designed for beginners but is still be fun for experienced RC pilots. If there is no wind, the champ is literally uncrashable (unless of course you crash on purpose). It's a three-channel plane meaning you have control over throttle, rudder, and elevators. I've heard of people adding ailerons but have never tried. Wind will cause trouble for the champ, but it can be a fun challenge to more experienced pilots.
The champ was the first plane I had, and was a great starting plane. Even though I have faster and more acrobatic planes now, the champ is still a lot of fun to fly because it requires little concentration. It's a great end-of-day plane.
The stock LiPO batteries included with the Champ are garbage. Only lasting about 7 to 8 minutes per flight in my experience, they require more time to charge and don't hold up over time. Having multiple batteries is a must, but I'd recommend avoiding the stock batteries (or the ones by E-Flite). While they work, it's almost $5 a battery and as described, they aren't reliable.
When buying lipos (trust me, you'll want at least 6), I'd recommend getting the Turnigy 1S lipos from HobbyKing.com. They are about $1.70 a piece, last longer, and are more reliable than the EFlite (stock) lipos. Overall, a great deal.
Because the Champ's foam is very thin, breaking or snapping it can happen easily. While it may seem simple, regular clear scotch tape does a great job at keeping the champ in one piece. Unlike glue, tape doesn't need to dry and doesn't add much extra weight. It's great for emergency field repairs.
For broken wings or tail, use foam-safe glue (Gorilla Glue works well) and transparent scotch tape. Put a small amount of glue along the crack, re-attach the broken section of the wing, and use tape to hold it in place along the outside. Make sure the wing is straight, of course.
Another part that has broken on my champ multiple times is the prop shaft. This can happen during hard nose-landings. Stripped or shredded propellers should also be replaced because they will limit the plane's speed. All of these parts can be found on amazon.com or ebay.
The stock motor is brushed, and isn't as powerful as the stock motor in the Parkzone P-51 or T-28. Using one of these motors in a champ is a very quick and easy upgrade. If you want a more powerful champ, this is also for you. The P-51 motor is significantly more powerful than the champ's stock motor, and is compatible with the champ. If your motor is getting old, I would recommend you get this instead of the stock champ motor.