I bought customized sofa from Rooms To Go like 6 years ago. I went to many different stores and sat on many different sofas because my main requirements were plush/comfortable and long enough for me to lay down on. RTG won out with this one, and it has a pull out bed which is not terrible in the fact that you can't feel the cross bar under the mattress. Not sure if they still do their iSofa customizing thing or not, but would recommend. I got to choose the fabric, pull out mattress type, and 2 pillows. I think it was $700, and they delivered it up to my second story living room.
2 or 3 weeks ago I went and helped some friends pick up a sectional sofa from Ikea, then we assembled it. The floor model sofa was more comfortable than the brand new one, but I guess that's to be expected after it's been sat on by thousands of people. In some time I expect theirs will soften up, too. To me it seems a bit overpriced for the build quality (some of the velcro strips that hold the cover on were about an inch out of where they should have been, but it was at least on the inside of the armrest between the frame, so not a problem once assembled), but given that it's reconfigurable/expandable and you can buy different/new covers for it it probably balances out value wise.