The author didn't specify how large his project was. If it involves a lot of servers then Gentoo's ability to basically "make your own distro" could prove very useful. You can't get much more flexible than that. Since the OP is coming from a BSD background that is an advantage for Gentoo as well.

On the other hand if the project just involves a small number of servers than Gentoo will likely prove more hassle than it is worth. In that case the conventional wisdom would be Debian. (or RHEL if you want to pay someone for support).