As stated above Jos A. Bank is good, but it is definitely a cut or two lower in thread count and material (thinner) than Brooks Brothers IMHO. Think Chaps vs. Ralph Lauren (Polo). If one is on a budget, a la just graduated, buy one or two suits to get ya going. If one is wearing it everyday, look elsewhere.
Cut wise they are tailored similar to Banana Republic (tall and not broad shouldered), but has more flexibility to accommodate wider ranges of sizes. Their blazers can tend to run a little small across the back, but I am stocky (Brooks Brothers workers well for me here).
Good luck.