Worth the trip to see though, you won't get the full appreciation of the baroque garden if you visit in winter as I did as all the flowers and rose bushes are securely wrapped up against the cold.
The Palace itself has been largely restored as it was destroyed in WW2 and then refurnished either with surviving furniture or with furniture taken from other German palaces of the same period so it isn't 100% authentic but, the restoration has been extremely faithful so you'd be unlikely to notice the difference if nobody told you.
Currently the Neur Wing (new wing) is closed for renovation and cannot be visited so could only see the main palace. Downstairs is done as it would have been in Sophie Charlotte's time and upstairs has been done in the style her grandchildren would have had. Also upstairs are elements of the German Crown Jewels on display.
The palace isn't as visually impressive inside as Versailles for example or the Ludwig castles of Bavaria but, definitely worth a look especially on a tighter timeframe that doesn't allow you to get to Potsdam.
The audio tour (which is free with your ticket) is excellent and highly recommended as well.