The 50 ml pouch of ink runs around $8, while a 40 ml glass bottle is $11. You get a nice savings from opting out of the glass bottle, but that just keep in mind that you'll want something to transfer this ink to if you get the larger pouch option.
Ink characteristics
This is an extremely well-behaved ink. Even though it feels dry in the Monteverde, which usually feels a bit more wet with most inks, it never skips a beat or has flow issues. I wish the ink was a tad more lubricated, but it's not a major complaint. Once I'm writing, I don't notice it, but it is fair to note since this pen is typically a wet writer. Strangely enough, writing with a Japanese F nib didn't yield bad results either. Really, the ink is lubricated just enough to provide a nice level of feedback between the page and the nib tip.
Again, the color of this ink is interesting. I'm going to stick with calling it a dusty purple, but it's so much more. Purple, blue, gray, and even a hint of green sometimes are some of the colors you can expect to see regularly. It's these types of color mixes that keep me very interested in an ink.