I don't know if this is any help to you, but from my experience...

CB2 is fine if you're doing a dorm or guest room, first apartment or seldom-used cottage. Very similar to IKEA.
Lots of foam, cardboard, staples etc...looks cute...but wears terribly. Very similar to IKEA.
But to be fair, I have never purchased anything from them, only visited their stores. Maybe some of their stuff is good but I haven't seen it. And though I am not permitted to tell you how I know this, they have a VERY high markup.

Room and Board, on the other hand, offers a much better quality. While the price is initially higher than CB2, their merchandise is made to withstand a fair amount of use. I have purchased their casegoods on several occasions over the years and found them to be of excellent quality for the money.
Several years ago, it seems that they decided to upgrade the quality of their upholstered line. I had heard (though not confirmed) that they used to use only one supplier (McCreary), and have since branched out to many different sources. From visiting their stores, I can tell you that it's not all identical quality, but they won't sell you a piece of junk, not even their lowest-priced lines.
As far as service...no problems here, the staff has always been knowledgeable and helpful.
Also, Room and Board is a licensed retailer for Herman Miller. This company is NOTORIOUSLY protective of their brand's image, so I doubt that they would associate themselves with any retailer that was not of a certain higher standard. In fact, they have been known to pull out of stores that have developed problems.
I know I sound like an unabashed cheerleader for RB, but trust me, I don't work for them. Just a satisfied customer.
BTW...they have floor sample sales twice a year...usually around June and December. Got some great deals, even of Herman Miller.

Lots to see in Chicago. Come visit us. But not in winter.


P.S....
Though you did not mention them, I would stay away from Chiasso. Horrible stuff with outrageous markups. There is a connection between them and CB2 / Crate Barrel. Again, I am not permitted to tell you how I know this. No, I never worked for them. Or any other competitor or even in the home furnishings biz. No axe to grind here, just an experienced and (hightly) opinated consumer.
And to be fair, Crate Barrel's quality is pretty good, just a bit pricey. I bought a Mitchell Gold sofa there that I'm still happily using years later.

Good luck.

I actually went with Room Board, I ordered it a couple of months ago. The furniture arrived yesterday. I am very happy their service and the quality.