Fast glow plugs?

Are these just new glow plugs or a special variety of glow plug?

If I replace the glow plugs I would want to get the glow plug reamer tool. I see performance products has them, they list 2 with a 100.00 price difference between the two. One at 49.89 and the other at 149.89. I wonder if it is only quality in the price difference.

J