Thunderlooper doesnt use LIMs, it has a weight drop launch system. It shouldnt be possible to black out on a launch either. Blackouts are caused by the blood going from your head and down into your legs. During a launch you are pressed back in your seat, not down, and therefore it shouldnt be possible to experience a blackout during a launch.
The only launched coaster I have ridden is Kanonen, which uses a hydraulic launch system, and I thought it was very intense. Short, but intense.