I also have neither, or have even heard either the 100 or the 150, but as much as those who have the VP100 really love them, I can think of two reasons why I would go with the VP150.

The 150 has no optional "upgraditis" feature, and the 150 is a bit closer to the standard Axiom 80hz crossover-to-the-sub point.

And yeah.....welcome!....and I guess the 150 "sounds" a little bigger, too, or so I've heard.