What are the best Room Accustic Treaments members have found?

GIK Acoustics Soffit traps dramatically improved the bass in my room by adding punch and enhanced definition.

GIK is the best! The free consultation is very helpful. 

Don't believe anyone who says that something thinner than a GIK panel can treat your room. It can't. It's physics.

+1 on GIK.

Jim Smith's "Getting Better Sound" is a handy reference for room optimization.

I've been working on The Room for the last year or so, I found a set of eight Aurelex 2' x 2' foam studio panels on line, made some cheap stands/frames to hold them up, got four concrete forming tubes, and moved these around the room to figure out what should go where, before buying from GIK. 

One problem I am not yet sure how best to solve is my front wall has a 6' x 6' window.  Initially I put up huge heavy drapes, which made for a nice dark background (both acoustically and visually), but as time went on I realized I missed the light, and also when I opened the drapes but left the blinds closed, it seemed to make for bigger sound stage.  And after 1.5 years, I realized that the drapes are fugly.  So I plan to buy some cellular shades plus a textured wood blind that will raise/lower over the blinds, hopefully have the choice and best of both worlds.  Might be TMI, but that's my room story so far.  Oh, and I dumped the rack in the front of the room, that was an instant improvement, probs bc it was Ikea.

If aesthetics are not a priority and you can live with the look of unfinished foam this is an inexpensive possibility:
http://www.nextacoustics.com/

The company I used is Audimute.I sent them a layout of my room with pictures and they advised me what I needed. Their stuff is also made to order and their prices are reasonable. Never talked to anyone personally, all emails were promptly replied, and I found their quality to be excellent.