BY offers several different cushion options (call "Formulas") in their range and they vary by model as well. The sofa you sat on may not have the same cushion core as the sectional you are considering purchasing. Also, back angles, seat heights and other factors come into play, so at best it VERY general to sit on a sofa and assume a different model sectional will be similar.
Can you customize? Somewhat, but you have to be careful because:
1) You've not tried the actual sectional you're considering customizing.
2) There are no 'do-overs' on customs.
3) All cushions - from every maker - will 'break-in' when new. I'd expect every cushion to soften a little with use.
Duane Collie
Straight answers from thirty-six years in the business.
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