Well, if you prefer mac os, you definitelly have a reason to do so. What is it? Can you easily switch to Windows?
What does it mean - powerfull? I have some 12" Dell refurbished with some embedded Intel and Linux onboard and it is powerfull enough for my needs. Do not ask yourself which laptop is more powerfull then other, rather ask yourself which one is powerfull enough for your application.
And of course - there are lots of very important properties and features other then performance.
I want to buy the better option because in future when i need performance i will have it.
Well, I think it is OK to estimate your needs for the (near) future. But remember that (lets say) CPU which is considered as highend today, will be considered as slow power-consuming shit tommorow. Computer hardware is really really fast progressive. You need to consider other aspects in the case of laptop, at least: power consuption (battery runtime), size and weight of machine.
You told that you prefer Mac. Why? Just UX, or are you using some apps on it? Maybe these applications do not have alternatives on Windows or maybe file formats produced by that applications can't be opened on alternatives correctly. So first question to answer is: are you
free to switch beetween OSes and apps?
Is it performance your only criteria? Why laptop then? Desktop is much more versatile, more powerfull and cheaper option. So this is second question to answer. If there are other criteria, please, let us know about it. We need to know to help you. If you do not know much about computers and cannot named your criteria, that's fine. Just let's talk about your regular computer usage.
- What do you use your computer for?
- What kind of applications are you using?
- Are you working at one place or you need to take-away? How often?