It's actually the same evaporator in both models so they're wrong and the S/V/C 70s are (so far) doing better than the 850s for other reasons. First, the 850s are older cars but Volvo made a few other improvements to the system with the X70s, very minor changes like cabin air filters and a different design for another idea regarding debris from the blower motor armature. Both design changes have been incorporated in 850 evap "kits" now sold by Volvo and available at dealers. I believe this latest kit came out less than a year ago and it also includes a replacement accumulator as well. Believe it or not, when given a choice most customers decline to purchase the improved kit vs just the evap only as it's more money.