Go with parallels, without a doubt the best you can go with. Very fast and feels native.
The downside if you won't be able to use a windows manager like WMII. Because parallels provide bindings for unity that makes the whole experience smooth and they don't provide bindings for other windows managers
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What is the best VM software for OSX? I tried using VirtualBox but it seems kind of slow and unreliable for daily use.
Go with parallels, without a doubt the best you can go with. Very fast and feels native.
The downside if you won't be able to use a windows manager like WMII. Because parallels provide bindings for unity that makes the whole experience smooth and they don't provide bindings for other windows managers
https://www.parallels.com/