The 6" scope costs a full $100 less, and so it's tempting. I know that those 2 inches translate into about twice the area. Intuitively, it seems like the image would be twice as bright, but I heard that human perception of brightness is not linear, and so perhaps it doesn't make that big of a difference. They both have the same focal length, fyi, and one is an f/8 while the other is an f/6. The 8" is technically affordable, but a little bit painful also. Maybe I'll just wait another 2-3 months.

Edit: Shipping is also a bit painful, at about $75. Also, do you think I should get a case for it? It's an Orion Dobsonian. Those add another $70 or so to the price. All of this adds up a bit, and I wonder how much luck I'd have finding a comparable Dob from a local retailer so that I can save on shipping.