Thanks, Bossnass. I'm really leaning towards that Big Agnes Sunnyside 2... I called Big Agnes today and apparently they only made this tent for REI (i.e. it's not anywhere on their website/catalog), and the material's a bit heavier than their usual tent but otherwise it's high quality. At 5 lbs 6 oz and a very reasonable price, I'm pretty tempted to go with this one.
Sidenote: What is with outdoor companies and three letter abbreviations??? REI, EMS, and now MEC...