Pros
Franklin will provide you with good exposure to a wide range of groups. At the very least, you can expect to grow your skill set. Franklin definitely values extended education (either training on new tools, business concepts or even post-graduate/MBA studies) and is willing to fund most learning ventures. It's a good place to be if you want to ramp up your experience. Also, the products are great -- the portfolio team is definitely the brain trust of the company.
Cons
In terms of career growth, there is little to no room for growth. For this reason, talent does not seem to "stick around" at Franklin (two years seems to be the max for true top performers unless you've sold your soul to the graduate/MBA education assistance program). In terms of management, most "leaders" were placed in their position based on the years they dedicated to Franklin (versus talent/intelligence/experience) so decisions made may not always be the "wisest". To put it frankly, not everyone at Franklin is all that bright and they tend to drag their feet to get anything done.