Of the two I like the Piranta, might take a look at the Torch or the Bolt too since its your first.
Just took a look at the Bolt - I'm guessing the main difference is blade thickness? Looks like the Bolt also accepts the regular blade also.
I have been looking into one also, I have a question which may be lame so I apologize if it is. Are these knives only used for skinning or do they hold up for quartering and deboning also? Again I apologize if that's an obvious or previously discussed answer, but the knives I currently use are not an option for backpack hunting, which is new to me.