Comb does not offer as much lateral (offset) adjustment, doesn't have as much toe in/out or pad offset adjustment. Comb also does not appear to have any back and forth adjustment. Ergosign does have a pitch adjustment, but it is so minimal that it doesn't appear to be much of an asset.
So we're comparing apples to apples, the Ergosign w/ recoil reducer is 2192 euro, or a hair over $3k. New PFS is $1295. So 2.3x the price. And that doesn't include customs or shipping fees (which the individual who was selling a used one on here estimated would be about $300). So now we're looking at $3300 vs $1295, or 2.5x the price. So yes, I was a little over with my 3x estimate (I was thinking they were closer to $4k w/ the recoil reducer). Ergosign also upcharges for lefties, PFS does not.
New grips for PFS are $240, new grips for Ergosign are nearly $800, so 3.3x the price. They also cannot be changed by the shooter, they need to be changed by the factory, something not required with the PFS.
Generic wood grip (ergosign) vs generic plastic grip (PFS) doesn't seem to be a value-added situation to me.
If you want a wood grip, you can have a completely custom one made for the PFS for about $1k, then you'd be into the setup for about $2k total, still $1300 less than the ergosign.
The ergosign stocks appear to be quite popular amongst international skeet and trap shooters. Not so much by any American games (skeet/trap/sporting). Then again, I have a feeling the shooters using them are pretty heavily subsidized for using the product to begin with, whereas with PFS, if you want one, you buy one, nobody gets a free ride.
So far, I haven't seen anything substantial that the Ergosign can do that the PFS can't. Yes, its a little prettier, but its not as adjustable, and is much more expensive. The resale value appears to be not as good as PFS either if you decide you don't like it.