I've just been out & about on some of the bumpier roads around here, and those 20kg Hagons are WAY too hard. Ouch, rock solid!
From what you're saying Scott, if the 18kg springs suit you at 225lb weight, I'm thinking the 16kg ought to be the better option for me, 60lb lighter - in spite of the Hagon man recommending the 18kg. I doubt they'd be soft enough to bottom out, and there's two notches of adjustment anyway. I was happy with the ride on the stockers, so really am looking for same but better, if you know what I mean..
I guess they'd change them again anyway if necessary, but it's shipping costs each time.