Training and Certification

I'm looking for some generic advice on choosing enterprise vs. service provider tracks. I've been discussing these tracks, and these environments with different folks I work with. This is what I've heard: while service provider environments have more interesting tech (MPLS, VPLS, big scale, big problems), they are typically very siloed engineering environments. While enterprise environments don't have as much of that aforementioned interesting tech, they offer more opportunity for an engineer to work on a more broad range of areas. Currently I work in an enterprise environment and have access to that broad range of work. I've never worked for a service provider. 

Whatever I choose, I want go to JNCIE for that track. I really like topics on the SP track even just from an academic standpoint. Do you guys think it would be a waste of time to go SP when most of what I'm doing is ENT? I realize it's more work. I'd definitely like to keep the door open to work in an SP environment if the right opportunity became available but I like the broad exposure I currently get from working in medium to large ENT environments. 

I work in a large enterprise now and I assure you they can be just as segmented and specialized as a large ISP.  I see the specialization is more of a function of the IT department size than the company being enterprise or service provider.

I would think the main driver for choosing certification as ENT or SP would be the Juniper gear you expect to configure.  ENT is more aimed at the SRX and EX type of configurations while the SP is more MX focused.

In general I find that certifications work best for me when they are strongly connected to my hands on experience.  So I go with the paths that focus on the gear I use the most.