Ok most people folks know I am a Mac user ( we have 2 Macbook Air, 2 Macbook's 3 MacBook Pro's, 2 Mac Mini's). That said I have the need to have access to windows (for testing web sites I create in Rapidweaver, and some genealogy applications). So what is the best way to run windows on a MAC? well I have tried them all so here is my take:
1. Bootcamp, allows a use to setup a seperate disk partition on you MAC (intel based only). This work well execept you must reboot you MAC to get to windows to run.
2. Parallels application (uses the virtual machine method) is a good product (I have been using Parallels since release 5 current release is version 13.x) it allows you to launch windows with in OS X. The current release is version 13 it supports Windows up to Win 10. The product support is good. Cost of the product is about 80.00 with release upgrades for 50.00 (49.99). Why are upgrades needed ? As Mac OS X is upgraded so also must Parallels. Other costs? Yep you must purchase a fully licensed copy of windows to install as a virtual machine. Parallels has better performance in OS X. It works best on Mac's with lots of ram and disk space. Win 8.1 runs very well in Parallels 9! Windows 10 works very well on the Parallels 12 and 13.
3. Fusion (VMWare product) application ( uses the virtual machine method) is a good product as well ( I have been a beta tester for a couple of releases) it also allows you to launch windows applications within OS X. The current release supports Win 7 with Windows 8 in testing. The technical support at times is lacking since VMWare first released Fusion. in the latest release that supports High Sierra has been performing pretty well . That said it is now stable. Cost of the product is about 80.00 with release upgrades for 50.00 (49.99), why are upgrades needed? As Mac OS X is upgraded (new releases) so also must Fusion. Other costs? Yes you must also purchase a fully licensed copy of the windows operating system to install as a machine. Fusion performance on MAC OS X is good (at best lots of crashes have been reported). The more ram and hard disk space you have on your mac the better.
4. Virtual Box (Sun Micro/Oracle) is an open source application (zero cost) that also uses the virtual machine method. Virtual box runs well on MAC OS X an allows for windows application to be launched from within Mac OS X. it supposrts Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7, Windows 8, 8.1, 10), DOS/Windows 3.x, Linux (2.4 and 2.6), Solaris and OpenSolaris, OS/2, and OpenBSD. Virtual Box also requires a licensed copy of the guest operating system to be installed. Support is better than Fusion and requires about the same amount of ram and hard disk space as Parallels and Fusion.
5. Crossover application is unique it actually installs it's own version of windows that has been optimized for MAC OS X (it also is only supports Win 95, Win XP, Windows 7, Vista, Server 2000, Server 2003). It uses what Code Weavers calls the bottle method (from the Wine origins). Applications are install via one of two methods via Cross tie application from with in Crossover (Codeweavers have lots of applications ported to run already) or via the standard exe file or cd rom method of installation. Pre configured applications (bottles) install all of the required windows apps and services as part of the installation process. Costs flexible from 39.99 with 1 month of support (no telephone support email only) to 59.99 12 months of email support with one free phone support incident. Performance is great! New version is release 13.70 it has been running great.
I have tested each one of these applications on several different Mac's in many different configurations. Good luck and I hope this helps out.
Crossover has been updated to 17.x and runs much better on 2009 and later Intel Mac's (including MacBook Air products). So if you have to run windows apps give CrossOver a try.