There were 3 leathers used for the sport seats. I don't believe the bolstering/support differed at all between them.
- Oregon leather was used on regular, non-M sport seats. They have that second stitch on the hip and thigh bolsters and no "M" logo
- New England leather was the term for seats from Extended Leather interiors and (AFAIK) did not have an "M" logo. It had the second stitch on the bolsters as well as an embossed pattern half-way up the back. I've never seen or felt this in person but read that it is softer than Oregon leather.
- Nappa Leather was used on Individual and Z4M interiors and is the softest, smoothest grain offered. Included the "M" on the headrest and no extra stitch or pattern.
In person I can definitely tell the difference between the leathers, although my job means I'm around them often and need to tell the difference. Not sure most people would be able to tell if not shown both side-by-side. That said, if you're after Imola interior, you'll have to get Nappa (Z4M).
Oregon:
New England:
Nappa:
