Visiting Forbidden City & Summer Palace - better solo at leisure or with a tour/guide?

If you are a history fan, it's recommended to hire a guide, who will tell you lots of history stories and anecdotes behind the grand architecture and amazing scenery. But you need to follow the guide's step and finish the visit in limited time period.
If you are more interested in the scenery and building themselves, there is no need to get a guide and you can travel at a leisure pace on your own.
Just make the comparasion and then the final decision.
Have a nice trip~