I've owned, for over a year now, a 7.1 Monitor Audio Silver setup with S8 fronts and I think the fronts are wonderful. However, the LCR has been very sensitive to placement and orientation. I now have the LCR oriented vertically at almost the same height as the two fronts and this has made things much better. The surrounds are decent for movies, but maybe not as good for music where the demand tends to be greater. The surrounds might behave better at ear-level instead of hanging near the ceiling.
I have not listened to the Gold series speakers, as they were out of my price range at the time, but I have heard that the Gold series are a noticeable step above the Silver series. So I would go for them over the Silver series if you can afford it. Plus, the Gold center is supposed to perform better than the Silver center.