For dress shirts, I'd avoid all three items you mention. I have a strong preference for Brooks Brothers wrinkle-free line (in slim fit; you don't actually need to be slim but they just look and fit better). Jos A Bank's wrinkle-free shirts are also very good, IMO. I find the Lands End wrinkle-free shirts to be neither high-quality nor wrinkle-free.
For sweaters, I really like all of the Macy's in-store brands such as Club Room, Alfani, and Tasso Elba (in increasing order of quality). As you mention, great prices on all this stuff this time of year.
"We have to encourage a return to traditional moral values. Most importantly, we have to promote general social concern, and less materialism in young people." - PB