Asics change a lot between generations. In year 2020 all S3's will be sitting on shelves.
No one will still be using them in 5 years, it's just that simple.
Why ?
Profitable will be same.
Than i will buy s5.
Because technology is rapidly changing. They won't be profitable in the future.
Do some research on your own so you stop asking questions that are deemed stupid.
All the S3's you buy will be worth almost 0$.
Than i will buy s5 .