Compared with the obvious alternative at this price point — a normal used pair in the middle of the market — €400 is ambitious here. Against your own comp set, it sits well above the €354 75th percentile and far beyond the €89 median, so this is pricing for a very fresh, premium, or unusually complete package rather than a standard used buy.
That said, this model is well-liked for its big, spacious sound, excellent noise cancelling, and luxurious build, and the listing’s 4 days old, with proof of purchase and 2 years warranty, adds real buyer protection and resale comfort. If the unit is genuinely as described and includes everything, the upside is condition, warranty, and near-new ownership history; just make sure the serial, warranty status, and physical cosmetics all check out before paying top-of-market money.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.