Linux compatibility with more than one Linux installed?

[Thomas Mueller]

I noticed on http://www.freshports.org/commits.php an update to the Gentoo Linux distribution.

I know there are other Linux compatibility ports in the emulators category.

Is it possible to install more than one Linux compatibility package or actual Linux installation and switch from one to the other?

I might want to install a Linux compatibility package and still be able to run Linux software through an actual Linux installation, separate from the FreeBSD Linux compatibility package.

Or possibly be able to compare one Linux compatibility package to another.

Tom