One obvious point ignoring all technology differences would be the license. I always like to have more options and even though I haven't used a BSD in maybe 5 years now, I'm still very happy they exist.

I'm most fond of OpenBSD and am VERY happy the project exists. OpenSSH alone makes the project a winner for me.

I also miss the documentation (man files) of the BSDs. They always seemed clearer to me than my current Linux counterparts.