Pros
If you are early in career or transitioning, the NSE role is great way to get your feet wet with networking. You have opportunities to learn more in other IT domains as well but not as intensely. When you are off, you are off. No being on call. There are tons of resources and opportunity for you to train and learn. The benefits are some of the best. If you work near a Meraki office, take the opportunity to go, it is worth it. The San Franciso office is the best. There is plenty of documentation public and internal facing. There is a process for handling cases that have no documentation which is very nice. You are not alone on this job ever.
Cons
Being an NSE day to day can become tedious. Most customers are fine, but you will eventually run into one that is difficult to work with. Everything is based on your stats like talk time and customer satisfaction which can be problematic at times. I left because there were no opportunities to move on to a different role. Cisco proper is pulling in the reigns tightly on Meraki, so the culture is changing not for the better. Being in the call queue all day can be tedious especially when it gets backed up and you do not get your scheduled down time. In the US you will have to work weekends occasionally unless you get someone to cover which is becoming harder and harder due to change in overtime policies.