Caching strategy recommendations

[thedentist8]

I would like to hear your opinion on the caching strategy for getting better performances with Panko.

I have complex objects that I serialize with Panko where 80% of the JSON output doesn't change, while the remaining 20% is dynamic and depends on the current request, i.e. the current user. I'm thinking if I should:
 

1. Cache the Active Record objects, pass them to Panko, and handle the dynamic data in the serializer. I'm not sure if this will be slow, as the objects will need to be transformed through Marshal for every request.
2. Cache raw JSON objects, and then pass them to Panko as attributes and consume them in the serializer form "context" and don't use the Active Record objects for the static 80% at all.

What would be a more efficient approach?