I usually cut down my footage to the top 2 or 3 laps. It seems like after about four minutes of track footage (unless crazy fast or tons of traffic) it starts to get boring. Nice job getting the camera angle so you've got the wheel/hands in the shot. I hate watching track footage where you can't see what the driver is doing.
i was thinking of getting two at first, one for the driver and one for the track in front, then i wanted three, an additional one for my feet/pedals. A fourth one go pro would be handy to have swell for cool rear view shots.