I also have a Samsung (and a Sony) Smart TV (again, not the exact same model) - They are pretty good for what they are - Provides an easy way to access various online streaming services such as YouTube, Netflix along with various "catch up" TV services from various TV channels and networks. That said, I tend to not use the smart features that often as I have a PC plugged into my TV for that sort of stuff (there's a couple of services that the TV does not support). Personally I wouldn't pay a fortune more for a Smart one, but at the time I bought mine the price difference was like £50 so that seemed worth it.
The only real issue I can see with Smart TVs is that you are at the mercy of Samsung to continue to support the various "apps" - If a provider (e.g. Netflix) changes their systems several years down the line and Samsung don't release a software update to your TV then Netflix will no longer work. On the plus side, except for the removal of Skype and some Samsung Social thing (neither of which I've ever used), this hasn't happened to anything on my TV yet.
My Samsung one is also pretty good in the sense that the "smart" stuff doesn't get in the way, unless you press the button to launch it you barely even see any of the smart functionality. This is a contrast to my Sony TV (which was a fairly early Smart TV, circa 2011) which could be a bit of a pain where you would turn on the TV and have to wait for 5 mins for it to do a software update.