Noticed that some VIGI cameras look identical and even their specs look similar, but the model name has some difference and some of them has different hardware versions with different updated firmwares. 

Just an example: VIGI C345 (V1) and VIGI Insight S345 (V1, V1.60). My only concern about VIGI surveillance system is that if I buy a large amount of cameras then suddenly TP-Link wishes to discontinue those models (Like what they do to their routers) and I get no new features and improvements but newer revisions get those features. It'll be definitely a loss project. (VIGI C345 (V1) is available in my area),

I'll definitely want to build a setup that'll work for at least 5-6 years without any issues and will get continuous improvement treatments from the company for at least 2-3 years before getting discontinued and not getting suddenly abandon.