I've got one of these, and think it's an excellent knife. You can certainly field dress a deer with it, but it seems a bit big for the task to me. However, don't let that discourage you from getting one.
It will hold an edge with the best of them, as well as being fairly easy to sharpen.
If you're wanting a fairly inexpensive knife that will be an outstanding blade for field dressing pretty much anything, and in my opinion be better suited to that task than what you're thinking about, might I suggest a Cold Steel All Terrain Hunter? I'm fairly confident that they're made by the same company as the BK-7. Whether it's the same steel I don't know, but it very likely is.