The Alien 500 clones make great cheap gimbal/camera platforms. The 450's use the same arms. Without the bulky gimbal and camera they can both be raced for fun if you race on an open course that doesn't have small gates. I really like the F330 clones for that.
I guess I am more into the GPS / waypoint / FPV / video aspects and you need a larger quad than the typical racer for that.
Some friends and I got some Parrot Bebop 2 FPV's for Christmas and indeed you can't make anything close to that for what they cost. 1080p video, FPV goggles, 25 minute flight time, 2km range, 60kph (37mph) top speed, GPS with RTB/H, electronically stabilized image as good as a gimbal, electronic camera tilt can look upward to straight down. Some really nice flight modes like "follow me" (GPS and visual) and waypoint flight (some are add-on purchases). A dream to fly. Take your hands off the sticks and it stops and stays where it is even in the wind. My non-RCpilot wife easily flew it FPV for 15 minutes.