I agree with the last two posts, a repro is awful. Just a couple of things to watch - check the chair for faults/damage with the shockmounts. A good test is to rock the back of the chair, if there is a large amount of movement one of the shockmounts could be broken (this is a professional repair which can cost Ł200-300). The second giveaway as the angle of the back rest, they should lean back slightly (vintage chairs often sag a little more) but it shouldn't be a huge angle! Good luck