How do you organize your work environment for testing?

[twilight]

Hello, it's not as clear for me as it should be,

I'd like to test my ports over several versions of FreeBSD (9.3, 10.3,
11 (upcoming), 12-CURRENT), but it's not to cool to keep 4 seperate
partitions for each version on my small SSD.

The obvious solution is to use qemu to run several versions, or several
USB sticks with enough environment to build and run ports.
Both solutions don't look perfect, as qemu will be kinda slow, and USB
sticks will require lots of reboots that is not to convenient.

What would you recommend?
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