I don't see any hassle in necking up brass, especially only 0.007".
I started necking up cases many years ago (1978) when I made .30 Gibbs cases from .30-06. I had to expand the case necks up to .35 caliber, then size them in a .30 Gibbs size die to make a false shoulder for the case to headspace on.
With .375 RUM brass being hard to get, I made a long taper neck expanding plug. With just a little Imperial size wax on the mouth of a case, I easily expand 7 mm RUM and .300 RUM cases up to .375. No annealing needed.
The only issue that I see with this process is the new case is not what is stamped on the head of the case. I always sort my loads by case headstamp. I haven't tested loads with mixed headstamps, and I haven't checked the volumes of the necked up cases.