The ones that are $9.99 are NON drop free. Generally, when they have used LE drop free G19 mags they're $12.99. I just ordered from them a few weeks ago. All the mags functioned flawlessly. I haven't seen anything that would indicate the springs need to be replaced.
"Posterity! You will never know how much it cost the current generation to preserve your freedom. I hope you make good use of it. If you do not, I shall repent in heaven that I ever took half the pains to preserve it."
– John Adams
Appleseed Project Instructor/Shoot Boss - Are you a cook, or a Rifleman? appleseedinfo.org