Sat down and listened to the Kanta 2 today. I was not able to compare them to any other manufacturers at the shop I was in. I listened to the Sopra 2's after.
As for the K2's they have a good sound stage and response on the highs but I found them lacking in the low end. I think it could be corrected with adding a sub to the line up but for me I want a full range set I don't need to add a sub too. I do think that this is part due to the 6.5" woofers.
As for the S2's they have an even better sound stage throughout the entire full range. I would have no problem running these without a separate sub. Considering the price difference in the K2's and S2's I think a set of used S2's would be a better option then the K2's.
Like I stated in the beginning though. I was not able to listen to any other brands at this shop.