Replacing or Repacking Leaky Stop Valve?

I have a leaky faucet stop valve that is soldered on. Once I cut it off with a tubing cutter, there will only be about a three-inch stub coming out of the wall. Is that enough pipe to slide on a new compression type stop valve?

Does anyone bother repacking old, leaky stop valves anymore? Does repacking guarantee that the packing nut will stop leaking?

Why waste the time trying to repair an inexpensive stop valve? Replace it with a newer 1/4 turn valve. Three inches is plenty of pipe stub to put a compression fitting on. You could also us a Shark Bite.