The Sims 3 was (and still is in my opinion) a great game with a lot of frustrating issues. If you can get past the fact that many computers (even modern gaming ones) have lags, freezes and crashes with it, I don't see it disappointing you game play wise.
Its like...the Sims - adventure version. The open world design makes exploring a great deal of fun and even after all these years I still find new things that I've never seen before while just wandering through the towns.
Keep in mind some do still experience performance issues though. Many of them can be, if not completely fixed, certainly lessened by the NRAAS mods. I've had very few issues with it since my most recent system upgrade, but it does still randomly crash from time to time. Just make sure to save from time to time and you should be fine.