I definitely have to agree with treasuretales on this one. Don't lock yourself into a purchase now, when you won't actually be buying for another year. Save up the money... pick a number. When you get to that goal, then seriously consider what is on the market in your price range.
Like TT said... technology is changing all the time. Keep checking the reviews here, keep asking questions, and you'll be able to narrow down what you need/want. But, before you buy, go check out a detector at your local hobby shop. See how it functions, and how it works, etc. It is always helpful to have someone near you that you can bounce an idea or two off of if you get stuck. Depending on where you live, there is very likely a member of this forum relatively close by, who will gladly travel to let you test drive a machine.
After taking your "preferred model" for a test drive, you might find that you hate the way it fits your hand, or balances, or the display... whereas another model that you didn't consider literally fits you perfectly.
steve