By using the thumb shot or what is also knows as long-distance spinner by Audley Walsh, what distance is very good or excellent? I know that by using the Hermann grip(ricky jay) or the method using to boomerang a card, a very good distance would be like 150 feet, but what about the thumb throw? I saw McBride and Juliana Chen using the thumb throw several times, so I also wanna know how far can THEY throw them in the audience?

A good thumb throw distance is 20 ft, although the flourish is impressive at any distance. Great throws are around 60 feet.

BTW, neither of them throw cards "into" the audience, and Chen doesn't use the Long Distance Spinner. Her's is based on her single card production, and is much more difficult.
McBride boomerangs cards over the audience (and back to the stage) and bounces them off the stage toward the side of the stage. A stray card could really do some damage if thrown at the audience. I have seen McBride live a few times and have seen him repeatedly boomerang 40 feet.

Joe