I don't have experiences of using it, but i have seen it in use plenty, and the main side effect apart from the normal anti-psychotic workings, is gain of weight. It can be very severe depending on the person, increase risk for other dissease, mainly cardiovascular risk. The main, and most scary, sequelae that is usually related to anti-psychotics is Tardive dyskinesia, which in few words make you lose the control on a few repetitive movements and it sucks. But, RIsperidone is one of the anti-psychotics less prone to give a patient that, due to being way waay safer, it is a much newer and more modern drug than say, haloperidol, and chlorpromazine.
As for Anhedonia, it is not a very common side effect from what i know, it depends on what you were using the drug for really, but usually when the medication is taken out, the symptoms go away. If you're left with it after making use of the drug, maybe it wasn't effective at all at treating your base condition, which in turn got worse and you developed that as a symptom, not a side effect. But that's just my guess.
I'm no psychatrist, so no idea!..