I took the plunge and bought the Premier Power Sled 14 and a Premier 25' Banner Tail. I've given it a few tries already, and the wind wasn't up to the task the first two times - too light and variable. The kite flew without the tail, but was having a hard time getting off the ground with it. Today was a different story though. I can't tell you the wind speed, but it was a decent breeze, and one of the steadiest I've ever seen at the nearby beach, both in speed and direction. It flew great with or without the tail, the only real difference being the angle of the line.
Just for the heck of it I also conducted a small experiment. I had my Canon point-n-click with me to get these pictures, so I put a little loop in the line (with the kite about 100' up already) and clipped the camera case onto it. I let out about 5' of line, just to see how well the kite would lift it - no problem. Definitely not a KAP rig, but it answered my question of feasibility.