Agreed, man! La Femme D'Argent is absolutely a masterpiece of the genre. Premier Symptoms is also a fucking incredible album. This was started a while ago when I didn't really know a damn thing about Downtempo, so things have evolved a little bit.
Blockhead is still amazing, Bonobo is still a lord, yet I've come to find alot of Quantic's stuff kind of uninspired.
If you can find time to look through all of his madness, Amon Tobin has some really high quality chillout songs, a great example of which would be "Day Trip". Check it out... http://www.youtube.com/watch?v=PU4sMhFwJpM
The Cinematic Orchestra have some incredible releases as well. Their albums "Every Day", "Man With the Movie Camera", and "Motion" are fantastic, but some of it might be a little too jazzy for some people. The track "Burnout" should sit just fine with everyone here, though... http://www.youtube.com/watch?v=Ed9CYDt99tA
Jazzanova's album In Between has alot of shitty songs, but a couple that melt your face: they are as follows... http://www.youtube.com/watch?v=cWCTn76q1xI&feature=fvst http://www.youtube.com/watch?v=lTeOVJb99FA&feature=fvst http://www.youtube.com/watch?v=uVlkFN6itzU
Lemon Jelly is in my top three artists of the genre, and I would recommend any one of their songs/albums, as they're all fucking gold. This one especially... http://www.youtube.com/watch?v=ZadtHGjKUSA
Similarly, everything Four Tet touches turns to gold, so listen to any of his albums and you won't be disappointed. http://www.youtube.com/watch?v=hWcmcSsry3E
This song should say it all...
Luke Vibert has some really old school, but really solid chillout albums from the mid 90's, the best one (in my opinion) being Big Soup.
Finally, Ulrich Schnauss' albums Far Away Trains Passing and A Strangely Isolated Place are really solid releases.\
Ps - http://grooveshark.com/#/s/Channel+1+Suite...x+/2HKGWT?src=5