In response to the original question, you'll want to use blast gates for optimal performance of just about any hobby-sized dust collector. There are tasks where you can get away with 2 or 3 gates open if you have a large enough DC (2-3HP).
I have an older 2HP JDS Cyclone DC ($1000 3-4 years back) that I am very happy with. By far you will get the best performance from Cyclone collectors since they separate 99+% of your waste in a bin before the impeller, allowing you to go for very long durations between filter cleanings/replacement. That said, the singe-stage collectors are a fine compromise for the average hobbyist -- just remember to be careful of vacuuming larger debris (blocks of wood, screws, etc.) as everything they suck up ultimately passes through the impeller.
The most ESSENTIAL feature to focus on, no matter what system (single-stage, or two-stage Cyclone), is 1-micron air filtration. Many base models only come with 3-5 micron filtration (or worse), which is just good enough to ensure that ONLY THE MOST HARMFUL dust remains in your shop. You'll have a cleaner-looking shop, but the air you breath will be just as bad for your health without 1-micron filtration.
Now that you are thinking about dust collection, you may also wish to begin thinking about ambient air filtration as well. An ambient air filter is an (often ceiling-mounted) air-cleaner that you power on when you enter your shop and leave running for several hours after. It will help remove harmful dust from the air as you create it -- especially the dust that escapes your DC system. It also helps to greatly reduce the amount of fine dust that tends to settle on every surface of your shop after a day of sanding.
It is good that you have dust collection on your mind as many don't consider this item until it becomes a problem. I know my father thought I was nuts when I bought my dust collector and ambient air ceaner BEFORE any of my larger power tools -- he could not understand why I would worry about dust BEFORE I was in a position to create alot of dust!