This may be a long shot, but did you use hub-rings when you installed your Rotas, as the Rotas have a larger hub size than the Honda wheels, and if you didn't mount the wheels super carefully and they are slightly non-concentric when torqued down, they may be causing some added stress on the wheel bearings. Also, did you torque the wheels (80ft-lbs I believe), or di you tighten them just short of a hernia?

Too much offset could also be loading the bearings unevenly, also, but there's 1000's of Rotas in use on Hondas, so I doubt that's the case. The Rotas are a lightweight wheel, but in the size you're using they prob weogh as much as your OEM wheels did, along with the heavier than OEM tires, the bearings are subject to some added stress, but again, I doubt that's the case.

I'd insist on using OEM bearings if you haven't in the past, and get another opinion. In the 45 yrs I've been driving, and w/ the almost 70 cars I've owned, I've only replaced wheel bearings on a '49 Olds rear end installed in a '40 Ford, and on a mid '80s Audi. Properly installed, they should last forever (almost).