a) I dont really see how you can (empty the boiler etc). You just put it away. But you could run a descale and clean before putting it away, and again when it comes out of hibernation.
b) If you mastered the operation of the Silvia then you should have absolutely no problem with the semi commercial as they are a lot more forgiving to the operator than a Silvia. Really, all you need do is work out the best setting for the machine with the M4D, and thats just fiddling around for a while seeing what happens to the brew as you change the grinder settings.
My advice therefore would be to just move it (Silvia) on. Do you keep your old tennis racket as a standby when you buy a much better one?
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