Respectfully, I disagree with the previous statement. On the Kutuzov 1st class group, the serial number is very weird and seem to have been altered. On the other group, there are also very weird serial numbers engraving and ugly conversions to say the least... This is not what I call problem-free groups. Even if I could afford, I wouldn't buy groups like these. But I guess these days, all the nice problem-free groups are in collectors hands and they keep them dearly... thus the reason why they don't show on the market.