When exchanging, one should not expect to be able to move from the unit assigned. Many resorts will make some effort to do so, but many more will not.
In particular, now that OL has been split into separate villages for RCI's purposes, you absolutely will not be moved from, say, West Village to any other. If you confirm a particular village, that's where you'll be.
Like any other large mega-resort in Orlando (e.g. Vistana) there will always be some rooms in dire need of repair. Heck, if you read the DVC boards regularly, there are some rooms there in need, as well. But, your odds of getting such a room are pretty low at Orange Lake, and reviews indicate most people really enjoy their stays.