I haven't heard of a hp downgrade. He's lushed over it for 2 years now. Lyra does have a new cartridge out, the titan, suppposed to be all/more the detail of the helikon with more warmth. It's pricey around $4500. I have a good friend who used the Koetsu Rosewood sig. These are both great cartridges, just a style thing. Really the best way on this is to try it, which I realize is a pain the neck.
Good luck
Good luck