As a precaution, I replaced the stock radiator on my 2008 XT Forester auto with an OEM unit at around 80 000km - Subaru were offering a good price on these units at the time. The car is now sitting on 125,000km and I have decided to replace with an all aluminum Mishimoto radiator and universal cooler for the ATF fluid.
The overseas forums tend to rate quality on the Mishimoto radiators as poor and many won`t touch them. This is particularly true of the Mishi caps and thermostats. As the Mishi radiator appears to be definitely superior to the OEM plastic units which fail eventually as a matter of course, I will fit the Mishi unit that I have bought. However, will probably replace the radiator and overflow bottle caps, and thermostat with OEM in the interests of reliability.
Has anyone experienced problems with the aftermarket Mishimoto radiators, caps, or thermostats and any advice in this regard?