Don't do it.You'd essentially be selling a car you dont really use to buy another car you wont really use thats got considerably less power but will cost you roughly around the same kind of money that the RS does.
I'd keep the RS.
The ST is a great car, but I'm not sure I could go backwards to one.
You be better off asking Tiny. He's had both (I believe) and will be able to give you a litte more insight
i sold my old focus st to get a big family car and bought an audi q7. missed the st like mad, couldnt get an rs due to been a 3 door , bought a fully spec'd st3 4 door and banked the changed.do you mean reliability ?