System 7 are great, I own most of their albums and they're one of my favourite groups. Steve's guitar playing can get a bit too much for me sometimes though, but usually he keeps it at an acceptable level. The Rainbow Dome Musick album is also great, a true ambient gem.
I was surprised to find out recently that Hillage/Giraudy had released an album in 2005 under another alias, called Mirror System. After reading reviews I bought it right away, and it turned out to be another ambient/downtempo gem. Recommended for you who haven't heard of it.