If you go by the bootcamp, there is a need to restart your MBA every time you switch OS. The pro is all your memory is allocate to whichever is the active OS at any time.
The hassle is as above; you working on a file in MacOS and need to use windows software, you need to save your work in MacOS and restart your MBA in Windows.
On the other side, you need to get Parallel in order to install Windows within MacOS (virtual machine). The good thing is you need not restart your MBA to use Windows. Windows is like an application with MacOS and you can use the Windows and Mac software at the same time as and when you like within MacOS.
However, your MBA memory is shared between the 2 OSes whenever you launch Windows in MacOS. You can allocate a certain memory to Windows in this case. Hence, you may need more memory to work more efficient. I would suggest 16GB in this case so you can have 8GB for each respective OS, depending on what program you are using at the same time.
There is no best better method, it depends on how comfortable you are with either 1. Some prefer the convenience of using Windows without the need to restart, but at the expense of memory (unless you have plenty of memory). Others have limited memory on their machine and hence, prefer the full memory allocate to the OS at any 1 time, so they opt for bootcamp instead.
Depending which method you use, you will still need to spend on Windows OS and Parallel if you go by virtual machine.
I'm not sure where to get the cheapest Windows or Parallel, or BT. Others may advise in this area.
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