It was launched in September 20, 2015.
at that time it was most liked phone for all kind of users.but as years pass out, technology has evolved a lot. but it still can compete to the present rivals.
I purchased iPhone 5s 16GB in march 2014, it was awesome at that time. camera is good. becomes grainy at max zoom. some bugs have also come up in due time.
the pros and cons according to the latest ios 9.3.2:
pros
8 megapixel camera also clicks good photos, in day light as well as in low light
1.2 megapixel front camera may sound bad but its not . it clicks nice photos in day light but not so good in low light
performance in overall is pretty good. no lags while using it.
very handy
cons
many bugs have been detected but most of them have been resolved
performance has slowed down after the upgrade to ios 9.1
fingerprint sensor respond well but lags behind when fingers are wet.