I personally replace my CPS every 3 or 4 years as preventive maintenance. When it comes to the RCM, it seems the ones manufactured before 2007 are the most problematic with the soldering joints/relays. You can see the date of manufacture on the RCM, the year is the first number if I am not mistaken not like a typical date in the US. If it is your daily driver, then it is best to buy a new one and send your old one for repair or if you get a good deal on a used one then send it for repair.