I have the Sargent and love it. Others have sent theirs back on account of fit issues.
You can read a lengthy review and discussion, with pics, of the Sargent seat here.
Nobody seems to have received a Corbin yet, so the jury's out, but the shape looks very close to the stock seat.
I believe both companies have money-back return policies for 30 days, so there's no real harm in trying both.
My guess is some folks will love the Corbin, some will hate it. Some will love the Sargent, some will hate it. Everybody is a different size, weight, inseam length, etc.
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