It's difficult to determine the definition of "soon." Back in 2006, 800MHz rebanding was happening "soon." It just affected us in SC this past fall, nearly 6 years later. And I don't think it's 100% complete process yet. You could very well get 2-3 years or more out of an analog scanner, or you could get 2-3 months. It's difficult to say. Purchasing a digital scanner now and taking a chance on a used radio (ebay, craigslist, RR classifieds), versus spending less on a new analog scanner and planning to upgrade to a digital model later, is a decision you'll have to weigh for yourself. It's a tough call.
Mike is right there in Pawleys Island area and can help you with local configuration files for the Uniden models. There are others of us that aren't in the immediate area that can send you GRE/RadioShack configuration files for the HC/GC area, but again you'd have to spend more (almost $60) to obtain the programming software and cable for the GRE/RadioShack models.
Good luck on your decision. And you're smart to ask before going out and making a purchase without due consideration.