We currently have a number of sites hosted on "spingen.com" servers. Our experience has been very good, up time along with the willingness of the Webmaster to tweak and adjust to my picky needs and help when I screw something up.
Any downtime we have experienced with Spingen.com has been schedule updates to the Plesk server which we are on, I know that they also have FreeBSD but our sites are located on one of their Plesk server boxes.
Currently I have 2 personal sites, the largest is CAWEBGuys.com
which burns up about a 2GB a month of bandwidth. Plus I have 6 client corporate client sites also hosted by them one which operates with a hell of a lot of email accounts.
Can't say much more than I have had only good experience with them.