I have both the MDR-EX90LP and the MDR-EX85SL. To my ears, they EX85s sound about the same as the EX90. The EX85s are less expensive because of less expensive components and less sound quality testing. I have been using the EX85s the most because they are lighter, have a short cord, and a more robust strain relief on the earbud. The EX90 and EX85 are the best earbuds that I have ever used in terms of sound quality, comfort, and stay in the ear quality. My other earbuds have included the CX300, EX71, EX81, MD33, MX500, and E3C. The EX81 sounded very similar to the EX71. Personally, I did not like the over the ear piece of the EX81. The EX71 has a very strong bass. The bass seems to overwhelm the other frequencies. The EX90 has an excellent bass that does not drown out other frequencies. The EX90 is significantly better sounding than the EX71/81. Because of the driver design, the EX90 tends to stay in my ear much better than the EX71 did. IMHO, for about the same price, the EX85 is a much better value than the EX71/81.