Is the Dynavector DV 10x5 as good as they Say?

I had the 10x4 (before upgrading to the XX-2), and, yes, it is as good as they (and I) say.
I can't imagine a better cartridge at the price, or even a lot higher. Clarity, dynamics, and tracking are incredible. You won't be disappointed!

I heard it when I was demoing my new amp and immediately decided it was my next upgrade.

It is a decent cartridge, but its list price in the US is way too high. If you buy it directly from Asian importer for around $200 - that's a different story.